Mai was born as Mai Hazuki, the male heir to the Hazuki family under Houichirou Hazuki and Rin Hazuki. He was trained in the assassination techniques of the Kirihito family, becoming acquainted with Shiori Kirihito. After coming into contact with the No-Name Grimoire in the Hazuki library, Mai was transformed into a woman and ran away, ashamed of what had happened. She changed her last name to Natsume and enrolled into the Military Academy one week later than usual. She developed her super-taste ability around this point, and became unable to eat most ordinary food.
Once she had joined the Academy, Mai became fast friends with Noel Vermillion, Tsubaki Yayoi, and Makoto Nanaya. She joined them for the Ars Magus aptitude test where Noel scored the highest marks in the Academy. The aptitude tester short-circuited as Mai accessed it, so Estella McKenzie, who was presiding over the event, decided to temporarily put Mai on a bridal course for future years. She soon found her way to her dorm after being warned by both Makoto and Tsubaki to eat before dinner since Noel was cooking. When she returned to her dorm, she met Kajun Faycott who began drawing various lines on her despite her protests. Mai learnt this was for data collecting since Kajun wants to learn everything she can. They both went to the cafeteria for dinner, where Kajun revealed that Noel made "death dinner". Mai took a taste and fell in love with Noel's cooking - later on, the group decided to bathe together, but Mai fainted once she saw their naked bodies. 
The Torifune Festival soon arrived, bringing all kinds of festivities. Mai learnt from Tsubaki about the festival and met Jin Kisaragi, Akane Teruhiko, and Taro Sasaga'e. They watched as Jin the main tournament (a game of "rock, paper, scissors") and set a plan into action for Tsubaki to win, with Kajun asking Mai to kiss all the other competitors to learn their thought patterns. Mai gave her first kiss to Makoto because of the latter's brashness with the subject - nonetheless, she continued with her job, giving the accumulated data to Kajun, who won the tournament instead of Tsubaki to allow her to spend more time with Jin in the student council.  A few days later, the group ended up lost in Torifune's lower levels after trying to find watermelons to eat. They choked on a smog of seithr, finding refuge in a nearby mansion where a mutated watermelon attacked the group, having emerged from Noel thanks to her swallowing a watermelon seed earlier. Mai saved the girls and were led by the mutant towards the Evolution Grimoire. Using a nearby sword, Mai cut a piece of the watermelon, ate it and learnt that it was seeking the Evolution Grimoire so it could turn into a melon. Soon enough, the group returned back to the dorms, where they resolved to find more Grimoires hidden within Torifune, with the hope that they could also find the Azure Grimoire, which Mai believed might be able to turn her back to a man. At this point, the group decided to name themselves Team Remix Heart. 
In the spring, there was mandatory cleaning of the student and faculty dorms. Tricked into wearing a maid's outfit by Kajun, Mai resolved to not get any work done as the penalty was a full course of Noel's cooking. Remix Heart were in charge of cleaning out Estella's room, where they discovered a secret passage to her hidden room filled with various feminine outfits. Inside, Mai fell, finding another hidden room that held the Ammit Cryas Grimoire within; looking into it, she saw her old body before dropping it. The group explained this all to Estella, who issued the maximum penalty after learning that they had been through her personal belongings.  The sports festival was right around the corner, and Team Remix Heart formed again with Makoto as their leader. Using Mai's super-taste, they resolved to find the Conversion Grimoire, which held the possibility of curing her condition.  They arrived in the lower levels again, but this time in a desert area. Makoto fell into an ant lion pit, so Mai rescued her at the expense of being burned around her chest by the hot sand. They were greeted by the Guardian, who congratulated their strong bonds, and offered them one of two gifts - the Azure Grimoire, or the Conversion Grimoire; Mai picked the latter, passing the test and they returned the higher levels where they all discovered that they had come last due to the time it took them. Due to the fact that they were the only team that actually brought back what was asked, Team Remix Heart were awarded MVP. 
The climate control in Torifune had broken down thanks to the Regulation Grimoire, reverting the city back to its naturally cold state. Taro slipped on some ice, dragging Team Remix Heart and Jin with him, and the group slid onto Akane's nearby igloo, which sent them hurtling off towards the lower parts of Torifune where a beach lay. The group enjoyed swimming in the ocean, using Golden Angel to create temporary swimsuits. They found the Regulation Grimoire while swimming, and fixed it, restoring the climate; they were soon picked up by an airship called by Jin.  In the library, Mai found the Hypnagogia Grimoire and was absorbed into a dream-like reality. After seeing a vision of her father, the dream turned into a nightmare, and Mai saw visions of her friend's futures, including Noel turning into Mu-12 and Tsubaki turning into Izayoi. After seeing them all fight one another, she woke up, and hugged her friends who had been watching over her, happy that the dream was simply a dream. 
Mai encountered the Aequivalentis Grimoire, causing her to gain amnesia; she revealed that she was a man, but the group thought it was a side effect of her new condition. She regained her memories after tasting the tears of all her friends thanks to her super-taste ability.  Kajun suggested that the group venture to the ninth level, where the Azure Grimoire was rumoured to be held - Mai agreed, and they journeyed down the city, but were separated when a fissure cracked open and swallowed the group, each one plummeting to a different level. When Mai awoke, she was found by Ragna the Bloodedge.  With Ragna, Mai explored the area, finding the Aedsqui Grimoire and its protectors. She kissed the statue, learning of the woman inside and its wishes. The woman, Elina, was reunited with her loved one through this act and her soul passed onto the next life. Mai was reunited with the others, but kissing the Grimoire made her ill as she contracted a surge of Azure from it.  She ran away from the others when Kajun suggested that she kiss them to see if her super-taste had left her, but tripped and fell onto Taro, inadvertently kissing him instead. Extremely embarrassed, she ran away. Kajun later revealed that Mai's super-taste had evolved, turning her into an Intermediary Grimoire - because of this, she had given Taro, Noel's cooking ability and taken his. Regardless, Mai had begun to feel better, and bathed with Remix Heart before being interrupted by Shiori Kirihito and Chachakaka.  She became properly acquainted with Shiori, falling for the assassin's lies about being a frail, weak girl. After learning that Shiori would be staying in her dorm with Kajun, Mai helped take care of Akane, Jin, and Taro who were bedridden after consuming Taro's tainted cooking. She soon realized Shiori's lies, recognizing the scent of poison on her, coming to the conclusion that she was sent to assassinate Jin. 
Mai personally tasted everything that was cooked by Noel to help cure the boys since she believed that Shiori had poisoned it. When serving it up to Taro, she became flustered, noticing that she was developing feelings for him. Because she came into contact with Ragna, his presence still lingered on her, sending Jin into a fury where he unleashed the Mucro Algesco: Yukianesa and began to make his way towards Mai.  Following telepathic instructions, Mai ran to the courtyard, narrowly avoiding every strike from Jin as Taro attempted to protect her. Soon enough, the sender of the instructions arrived and forced Jin to faint using an Ars - this man was Professor Cypher Albar.  Later that evening, Mai and Taro had a heart-to-heart conversation, bringing a smile to her face before they left to return back to their rooms. On her way, Mai was met by Shiori and Chachakaka, who revealed to her that they were sent to assassinate Jin. She beat the both of them using Kirihito techniques, hitting the human assassin with some of her own poison. Mai sucked some of the poison out, learning of her childhood - she hugged her would-be-assassin, comforting her and letting her cry in her arms. 
As she was involved with the creation of the various icebergs that Jin had made, Mai was stationed to look after it and the various pools of water dripping from it with the rest of Team Remix Heart. She was attacked by a small Torifune panda but managed to stave it off. Looking at Taro being happy throughout the day made Mai smile.  A few days later, Mai was introduced to Carl Clover, who took an immediate shining to her. The girls prepared her for a date with Taro after warming her to the idea, but she was stood up due to circumstances outside of his and her control. By this point, Chachakaka had deduced her identity and found Mai alone where she attempted to assassinate her as per Houichirou's orders.  Mai put up some resistance, and Chacha easily gave up when she came to realize Mai's strength, and left. Mai turned, and saw Relius Clover behind her, who intimidated her by talking about her soul. Taro finally arrived, but he was attacked by the rest of Team Remix Heart who berated him for being late. 
The revelation of hearing that her father had sent assassins for her had sent Mai into a spiral of depression, unsure of who she really is and knowing that she cannot confide her secret with even her closest of friends. She was attacked by an alchemic creation and was saved by Cypher, who had sicced the monster on her to begin with. She revealed to him about being the Intermediary Grimoire, and he handed her a device to monitor her body.  Survival training for the first years soon began and Mai was teamed with Shiori and Kajun - the goal was to defeat the Mountain Jellyfish that lay at the top of a nearby mountain. Mai noticed how good a team Shiori and Kajun made, and the trio were soon assaulted by the jellyfish. Thanks to Makoto, Noel, and Tsubaki distracting the beast, Mai was able to taste it and kiss Shiori to pass the knowledge of its poison to her - she quickly defeated it. The beast soon awoke again, and attacked them, but the group was able to stop it once more, soon going to Estella and finding that they had passed the survival training.  The device Cypher had given to Mai began to react, and she was sent into an unconscious state. She listened to Cypher torment her as he told her how he was going to feast on her heart. She began to talk to the No-Name Grimoire within her, who revealed that she had been transformed by it in order to host it. Knowing her friends were in grave danger, Mai fully fused with the Grimoire, accepting its power and breaking her comatose state. 
Now awake, Mai realized that everyone knew that she was previously a man because of the Ammit Cryas. Regardless, she broke a barrier around her and her friends, and came to fight Cypher. She fought against his Alchemy, barely landing any attacks due to his complete mastery, and being forced to defend herself from his onslaught of attacks using a quickly made sword and dagger. The rest of Team Remix Heart hugged her when Cypher was finding time to recompose, all telling her that they still loved her, regardless of her sex.  Cypher swallowed her up into the ground, making Mai and Shiori land near the cauldron of Torifune. She continued to fight the Alchemist, learning of his plot to use the people with the academy as a catalyst to create the Burning Red Grimoire. Shiori took a deadly blow for Mai, who had an incomplete Burning Red taken from her by Cypher (created through her fusion with the No-Name Grimoire). Mai fell unconscious after witnessing Cypher use sorcery from the Grimoire, and was later rescued and sent back to her dorm. When she awoke, she discovered Cypher had disappeared; Mai talked to the rest of Remix Heart, and learned that she was no longer the Intermediary Grimoire, and began to cry when she realised what great friends she had made. 
Now in her second year, Mai was invited with Tsubaki, Noel, and Makoto to Jin's medal awarding ceremony in the 2nd Hierarchical City of Iwatsuchi. Jin had become the "Hero of Ikaruga" by this point, ending the Ikaruga Civil War. Mai met Kagura Mutsuki, and ignored him when he started hitting on her and the rest of the girls. They soon met Hibiki Kohaku who immediately put them all to work with preparing for the ceremony. Now by herself, Mai was lured into the ninth storage under the faux orders of Hibiki - when she arrived, she saw that they were actually ordered by Meifang Lapislazuli, who told the girl that she wanted her body.  Meifang began to assault Mai, but she was saved by Kagura, who told her to run, so she did, but Meifang still caught up to her. Kajun's voice called out to Mai, and the Gallia Sphyras: Outseal appeared in front of her - Mai grabbed it, her pain now eased, and she fought against Meifang for two straight minutes before being teleported out of the area by Kajun. When she awoke, she asked her friend where she was and what was happening; Kajun told her that the Zero Squadron is hunting her down, and that they are headed to Sector Seven.  Kajun further explained that she works for Sector Seven under Kokonoe, who Mai did not believe to actually exist.
The two girls managed to board a monorail destined to the 13th Hierarchical City of Kagutsuchi by stealing NOL uniforms and having an imperial decree to allow them access. Kajun explained that Mai's body is the No-Name Grimoire, and that she can become any Grimoire or gain any kind of power if it's put into her, and she also explained about her weapon, Outseal. The two came across a Boundary Interface Prime Field Device coffin, and the NOL soldiers aboard caught up to them, threatening them before a door was blown down, revealing Jubei.  The old beastkin fought off the soldiers before Mai attacked him, being controlled by Outseal. The cart containing them was soon blow apart by another NOL soldier - the group fell into the snowy mountain below, and Mai awoke being watched by the girl who was inside the coffin.  Mai summoned new clothes to wear that Kajun had given her , and decided to get to know the girl, naming her Bell and taking her to a nearby cavern where she gave her some rations and her coat to warm her up for the night. The following morning, the two girls were found by Ragna, who did not recognise Mai from the year before  - he attacked her, grabbing her by her throat as she blocked him from getting to Bell. Both Shiori and Taro came to her rescue, saving her from the Grim Reaper. 
The skirmish between the group and the Grim Reaper was soon interrupted by Fuzzy, a vampire, who summoned ghouls for the group to fight while he personally battled Ragna. Mai was unable to use Outseal due to it being unfinished and deadly to her after multiple uses, so she was protected by Kajun  - Mai was in a trance, not noticing the summoning of a Bone Dragon as she looked at Ragna, who possessed the Azure Grimoire. Bell slapped her out of it , and Mai threw Outseal at the Bone Dragon and Fuzzy, piercing both with wounds that would not heal. Mai was protected by a killing blow from Fuzzy by Ragna, and she interrupted him activating the Azure Grimoire, annoying Fuzzy greatly.  She began to attack him, using a smokescreen created by Kajun as cover to land a sharp blow to the vampire, defeating him - she lunged at him again, this time stopped by Meifang herself, who took the blow straight on her palm. Soon, the group were surrounded by the Zero Squadron, and they were teleported away by Rachel Alucard. Mai, Bell, Taro, Kajun, and Shiori awoke in a grassy plain within the 11th Hierarchical City of Shinatsu, with the Hazuki estate in the distance. 
Mai and the group travelled towards her former home, where they were met by Julian, one of the maids - they went inside the mansion where Rin, Mai's mother, threw herself at her daughter, happy to finally see her home. Mai responded to a calling from her father, and visited him in his study - she apologized for tarnishing the family name, and he screamed at her for being bested by Meifang. Houichirou offered her a test - make him take one step back, or he will hand her over to the NOL. She accepted, but was bested by her father's incredible strength. He gave her one last chance to fight him, but without Outseal, saying that the match would resume in one weeks' time. Rin resolved to train her daughter for the ordeal.  The training included Rin using Vision against her daughter, but Mai refused to learn it, instead deciding to take on Houichirou without the use of it even though she could learn it in a week using No-Name. Mai talked to Kajun in the library where she transformed from a man to a woman, talking to her about her father, and later facing him before being interrupted by Kokonoe and Litchi Faye-Ling.  Kokonoe offered Mai a choice - be protected by her stubborn father, or join Kokonoe and grip her future. 
She chose to go with Kokonoe and the group ventured towards the cauldron of Shinatsu since mass teleportation was not available with such a large group. They were assaulted by Fuzzy, who kidnapped Bell and took her to the cauldron through a light - Mai followed, becoming separated from the others. There, she found herself at the cauldron, staring down Meifang and a large group of Fuzzy.  The Fuzzy around her began to play with her, taunting and teasing, never giving any real effort to their attacks; she did manage to wound one, earning Meifang's slight praise. The leader of the Zero Squadron began asking her about the civil war, and revealed that she wanted to create another Gigant: Take-Mikazuchi. Mai called her insane, and snow fell in the cauldron, signalling the arrival of Jin who had been sent by Kagura to take-down Meifang. 
Jin took on Meifang, commanding Mai to protect Bell and to fight off the Fuzzy army. The young girl told Mai that she was going to dispose of her body by throwing herself into the cauldron, stopping Meifang from being able to realise her plan. A group of Fuzzy attacked Mai and she lost sight of Bell - only seconds later she was protected by the Arma Reboare: Muchourin. Mai heard Bell's voice, noticing that Outseal was much stronger than before; despite this, she could not see her anywhere. In reality, Bell's soul had been transported inside of Outseal, and her body was now inhabited by Trinity Glassfille, who ordered her to continue fighting. With Outseal's new power, Mai threw it at Meifang, puncturing her shoulder, which was followed up by an attack by Jin. Meifang had finally lost all her composure at this point. 
Meifang ordered the Fuzzy's to attack, and they crumbled into dust, forming arms that ensnared Mai. She awoke in a completely different scenery, being surrounded by flames and corpses. Mai called out for Bell and Jin, not finding a response from them, but instead being met by Meifang. The Colonel told her of her dream, and how she desired to create a world extinct from conflict for the sake of the Imperator. To do so, she would absorb Mai and become the 'strongest weapon'. At this point, Mai understood that Meifang desired to turn herself into a Nox. Shiori, Taro, and Kajun came to her rescue and the four of them fought against the Colonel, with Mai eventually dealing a killing blow with Outseal, also seeing a mysterious woman look down at Meifang. The area around them began to collapse and they were returned to the real world. Thanks to Akane, Mai was able to reunite with Tsubaki, Noel, and Makoto. She soon returned to the Military Academy to continue her second year. 
After graduating at the Academy, Mai went missing, presumably to formally join Sector Seven alongside Kajun. She would rarely bump into Kokonoe during her tenure with the company. She also lost contact with Taro. 
Heir to the Duodecim's "Hazuki" family, and a classmate of Noel and her friends during their days at the Military Academy. From a sudden incident involving a certain grimoire, his body was changed into that of a woman's. After the incident, she accepted her condition and looked positively to the future. To protect her friends, she wields the Legacy Weapon "Gallia: Outseal" and faces danger head-on. 
Act 3: The Replacement Blue
|Stage 3: Litchi Faye-Ling|
Mai: This is... Kagutsuchi's business district? I've heard about it, but this space is transitioning... Heh, this makes my map useless. Am I ever going to find what I him...? Hm? Isn't that... Um, excuse me... You're Professor Litchi Faye-Ling, formerly of Sector Seven, correct?
Litchi: U-Umm, well yes, but... Have we met before?
Mai: My name is Mai Natsume. I heard about you through Professor Kokonoe...
Litchi: Professor Kokonoe...? Then I assume this isn't a little friendly visit. What does she want with me?
Mai: Please, I don't mean any harm. I want you to tell me where I can find Relius Clover. You are working with him at the NOL, correct?
Litchi: Where Relius Clover is...? Do you mind if I ask you something? Why are you after him...?
Mai: To protect my friends, and...
Litchi: Friends...? Very well. But... I have no intention of giving up that information so easily. How about you earn it?
Mai: I'm not sure what it is you want, but... Why don't we stop this?
Litchi: What a shame... Notice so soon?
Mai: Well, you didn't exactly try to hide it...
Litchi: I apologize. But I needed to make sure you were really qualified to meet Relius Clover. And it looks like you pass.
Mai: Huh...? Then you're going to tell me--
Litchi: But... I'm telling you this for your own good. You don't want to get involved with him... It looks like you're a little... "different," and Relius Clover only sees people as research materials. If he sets his sights on you, you'll be in danger.
Mai: Thank you for your concern, but I need to find him. For the sake of my friends.
Litchi: If you have one thing, it's resolve... Very well. I'll tell you the last place I've seen him. But don't forget what I've told you. Please be careful.
Mai: Th-Thank you very much.
|Stage 6: Makoto Nanaya|
Makoto: Ah, there you are. Looks like the intel was good.
Mai: Makoto!? I thought you were in the middle of a mission... What are you doing here?
Makoto: What am I doing here...? That's my line. Why are YOU looking for Relius Clover?
Mai: Heh, so the professor spilled the beans... I was hoping she wouldn't.
Makoto: I don't know what your reasons are, but... I think you know what this means. I'm stopping you from going any further. Because you're my friend. I know Relius Clover. And I can't let you go near such a dangerous man.
Mai: Makoto... I appreciate your concern, but... I'm sorry. I have my reasons, too. There's something I need to confirm with Relius Clover myself. So... ...I can't back down from this fight!
Kajun: Stop. STOOOOOOOOOOP!
Mai: Kajun? Thank goodness. The transmission went through.
Kajun: Don't "thank goodness" me! What on earth are you two doing!?
Makoto: U-Umm that's...
Kajun: Mai. Makoto is worried about you. And you somehow have the nerve to fight her? Punch her!? This is unbelievable.
Mai: I-I'm very sorry...
Makoto: What!? Me too?
Kajun: I will be sure to support Mai in her affairs. There is no need for you to worry.
Kajun: I agree, Relius Clover is a very dangerous man. But Mai and I aren't going to simply let him have his way.
Makoto: Kajun... ...Fine. I'll believe the two of you. But if something goes south, you have to promise me you'll call for help. I'll come running.
Mai: Of course. Thanks, Makoto... And thank you, too. Kajun...
Kajun: I-I simply want to see how well my reconstructed spear will do. That is all! And if I get to test it on the infamous Relius Clover, why... There's no better test subject in the world. So, remember that!
Mai: Yeah... Thanks.
|Stage 7: Platinum The Trinity|
Mai: Kajun, anything?
Kajun: ...No. I'm not getting any abnormalities in the seithr readings, either. Not a sign of Relius Clover anywh--
Mai: Hey, isn't that...?
Kajun: What is it, Mai? Have you found something?
Mai: Um, Kajun... You mean you can't see her? What's going on...!? Hey, Bell... Err, was it Platinum? What are you doing here? Aren't you usually with Jubei?
Luna: What the hell's YOUR problem! And why do you know about Master Jubei!?
Mai: Huh? Why...? Oh, of course. You don't remember anything...
Sena: Luna, this person's real suspicious... I think she might be a vigilante or something. After Jubei, maybe...
Mai: (This is odd... The moment she directed her intent towards me, her existence became stronger. Is the only reason I can see this child because of... The grimoire?) ...One way to find out. I'm really sorry. This is a huge gamble, but it's the only way I can think of right now!!
Luna: So, you wanna piece of this!? Let me warn you, as long as Luna's still breathing, I won't let you lay a finger on Master Jubei!
Kajun: What...? The signal suddenly appeared...! What's happening right now!?
Mai: Her existence is becoming stronger. Thank goodness... Looks like it worked.
Luna: Dammit, what the hell's your problem, fat tits!
Luna: Don't you play dumb. I know you're gonna try and seduce Master Jubei with those massive tits of yours! Oh, Jubei... Don't be fooled. They're just boobs... Why... Why...!? Why is Luna's boobs so...
Sena: Stop it, Luna. Complaining isn't going to change the truth...
Mai: Uhh, would you mind. Um... Listening to me?
Luna: Shut the hell up, Sena! Luna knows that, too!
Mai: Hehehe... Well, I suppose you've never really listened to others, have you? But your expression is much more...lively, now. Good.
Luna: You think you know me or somethin'!?
Sena: We're like the complete opposite of you...
Mai: W-Well, if I start from the beginning, it could take a while...
Luna: What the hell!? You just disappeared!!?
Kajun: Mai, what's the matter? MAI!? Oh no... How could I have let this happen...!?
|Stage 8: Relius Clover|
Mai: Whoa that scared the crap out of me... What just... Huh? Don't tell me this is... The cauldron? Kajun, can you hear me? Kajun? ..No use. Was that teleportation magic just now? It felt a little... Different. ...!?
Relius: I have no idea what you are. But would you mind staying out of my way.
Mai: Relius... Clover!
Relius: Oh? You know me...?
Mai: That's not all. Our paths have crossed before, but... I suppose you don't remember anything you don't find interesting. You're the one who brought me here.
Relius: That vessel is in a very interesting state right now... And I really don't want any more variables affecting my subject.
Mai: Interesting...? Subject...!? Do you treat everyone around you like objects...!? Don't mess with me! Looks like I need to take you down after all... Relius Clover!
Mai: You're strong...! But I'm not done yet!
Relius: ...You have the raw potential of a vessel... But you are still incomplete. No... You want to be incomplete...?
Mai: Shut up! Don't you dare Observe me with those eyes! I'm... We're not THINGS!
Relius: I'm afraid you are. All people are things. Things to be Observed by me.
Mai: ...!? That's why... That's why you built the military academy, too!?
Relius: ... Hmm... That's right. You're the thing that failed to become a grimoire. But that soul has become too close... To a woman. Or perhaps that is the reason you are incomplete...? Heh heh heh... You are much more interesting than I thought!
Mai: Answer me! The military academy--
Relius: My interest in you is quickly increasing. You're right... That "place" is designed to Observe souls... I created it to gather all those with high aptitude in one place. ...Makes it easier for me to Observe, you see... And some other benefits. Besides... Mutual intervention can lead to some very interesting souls. Wealth, race... None of that really mattered to me... I simply wanted those adept with Ars Magus. ...For my experiments.You. The professors... Everything that existed in that space... ...was nothing more than a test subject for me. Not to mention... I was very curious how No. 12 would do... How she would change living in a "human" environment. What do you call her again? Noel... Vermillion?
Mai: ...!! I will never... NEVER forgive you! YOU!
Relius: ...Give up.
Mai: Wha...! My body... Won't move! What's...!?
Relius: Once you have become a grimoire, you do not stand a chance against me.
Mai: Relius... Clover...!!
Relius: You've got quite an interesting soul... I look forward to seeing your growth.
Kajun: Mai... Mai!
Mai: ...!? Where am... I?
Linhua: No, don't move so quickly!
Kajun: Mai, are you alright? I'm so sorry, I let my guard down and...!
Mai: Kajun... And who are you?
Kajun: This is Litchi Faye-Ling's assistant.
Linhua: You bet'cha. This is Doctor Litchi's clinic. You got beat up pretty bad, girl.
Mai: Clinic... That's right, I... fought Relius Clover...
Kajun: ...So, you did see him, after all.
Mai: Relius Clover... He's dangerous. I need to stop him. To protect everyone, I need to stop him... We can't let that man do as he pleases!
Kajun: Mai... What do you intend to do?
Mai: We need to meet up with Professor Kokonoe. There has to be something we can do. He's not going to bring the Day of Recknoning upon us with those eyes... ...We're going to fight. With everyone.
Like all the other chosen, Mai was absorbed into the Embryo alongside Kajun. Mai was ordered to Kokonoe's lab, and was given data pertaining to a mission that involved contact with Noel, Tsubaki, and Makoto – Mai accepted although decided to wait on getting back into contact with them.  Like all the other chosen, Mai was teleported by Nine the Phantom to Ikaruga, far from where she was in Japan.
She found Noel by a roadside and took her to a small house where she looked after her. When her former classmate came to, she explained the events that had just transpired to Mai. After some begging, Noel gave into Mai's desire for some food that her super-taste could withstand.  The following day, they ventured together to Kazamotsu, and although they enjoyed the atmosphere, their enjoyment was cut short by Hazama, who had come to take Noel. Mai fought Hazama but was soundly beaten by his mastery of the Geminus Anguium: Ouroboros. For the second time in her life, Kagura came to her rescue and they went with him to Yabiko.  There, they met with Kokonoe and Tager, both of whom Mai had not seen in a while, so she enjoyed the reunion.  She was directed by Hibiki much later on to an airship where she would be sent to guard Homura Amanohokosaka, the Imperator of the NOL. 
Mai was last seen in the new world created by Ragna, helping Kajun and Litchi bring Platinum to the latter's clinic. 
- BlazBlue: Remix Heart, Chapter 01
- BlazBlue: Remix Heart, Chapter 02
- BlazBlue: Remix Heart, Chapter 03
- BlazBlue: Remix Heart, Chapter 04
- BlazBlue: Remix Heart, Chapter 05
- BlazBlue: Remix Heart, Chapter 06
- BlazBlue: Remix Heart, Chapter 07
- BlazBlue: Remix Heart, Chapter 08
- BlazBlue: Remix Heart, Chapter 09
- BlazBlue: Remix Heart, Chapter 10
- BlazBlue: Remix Heart, Chapter 11
- BlazBlue: Remix Heart, Chapter 12
- BlazBlue: Remix Heart, Chapter 13
- BlazBlue: Remix Heart, Chapter 14
- BlazBlue: Remix Heart, Chapter 15
- BlazBlue: Remix Heart, Chapter 16
- BlazBlue: Remix Heart, Chapter 17
- BlazBlue: Remix Heart, Chapter 18
- BlazBlue: Remix Heart, Chapter 19
- BlazBlue: Remix Heart, Chapter 20
- BlazBlue: Remix Heart, Chapter 21
- BlazBlue: Remix Heart, Chapter 22
- BlazBlue: Remix Heart, Chapter 23
- BlazBlue: Remix Heart, Chapter 24
- BlazBlue: Variable Heart, Chapter 01
- BlazBlue: Variable Heart, Chapter 02
- BlazBlue: Variable Heart, Chapter 03
- BlazBlue: Variable Heart, Chapter 04
- BlazBlue: Variable Heart, Chapter 05
- BlazBlue: Variable Heart, Chapter 06
- BlazBlue: Variable Heart, Chapter 07
- BlazBlue: Variable Heart, Chapter 08
- BlazBlue: Variable Heart, Chapter 09
- BlazBlue: Variable Heart, Chapter 10
- BlazBlue: Variable Heart, Chapter 11
- BlazBlue: Variable Heart, Chapter 12
- BlazBlue: Variable Heart, Chapter 13
- BlazBlue: Variable Heart, Chapter 14
- BlazBlue: Variable Heart, Chapter 15
- BlazBlue: Variable Heart, Chapter 16
- BlazBlue: Variable Heart, Chapter 17
- BlazBlue: Variable Heart, Chapter 18
- BlazBlue: Central Fiction, Mai Natsume Victory Quote Vs Kagura Mutsuki, Act III
- BlazBlue: Central Fiction Consumer Edition Official Site (JP), Story - Mai Natsume
- BlazBlue: Central Fiction, Story Mode, Episode 003, Chapter 015, Sub Scenario 1
- BlazBlue: Central Fiction, Story Mode, Episode 006, Chapter 041
- BlazBlue: Central Fiction, Story Mode, Episode 006, Chapter 050
- BlazBlue: Central Fiction, Story Mode, Episode 007, Chapter 055
- BlazBlue: Central Fiction, Story Mode, Episode 010, Chapter 080, Sub Scenario 1
- BlazBlue: Central Fiction, Episode 012, Chapter 100
|Other (C-series)||Edgar and Claire Vermillion ·Ellen Nelson · Four · Francis and Rosenne · Lao Jiu · Pakumen & Terumen · Three · Two|
|Remix Heart||Elina · Guardian ·|
|Variable Heart||Julian ·|
|Alternative: Dark War|
|Crossover Characters (BBTAG)|
|Persona 4 Arena/
|Under Night In-Birth|