Thirteen years before the Embryo Incident, Ripper was a sadistic serial killer. He was captured by the police and was being transported. Suddenly, Ripper developed his Drive and killed all but one of the police guarding him and escaped the van. He then broke into Yuki Himezuru's house and killed her parents. As he was about to kill Yuki, Kazuto Kotetsu, the one cop who survived, arrived and shot him, saving Yuki. However, Ripper survived the bullet wound and managed to escape.
Code: Embryo, Lost: Memories
Ripper was first seen digging through the corpse of a Union until he found their crystal and ate it. 
Two days laterm, he broke Drei's barrier and brutally killed Akio Osafune, eating his crystal. Realizing Ripper was in phase zero, Drei requested that he “release the Grimoire.” Ripper refused to do so unless it was interesting and called out to speak to Sechs instead of Drei.
The next night, Ripper attacked Touya Kagari, Es and Mei Amanohokosaka. After throwing a knife and a smoke bomb, he appeared behind Touya, asking about the Grimoire but was knocked away by Es. He was pursued by Es, who followed him into a building. He threw a Molotov Cocktail at her but was interrupted by Avenge. Once Touya and Mei arrived Ripper decided it had gotten boring and escaped. 
The evening after Akira Kamewari ripped his crystal out of his body, Ripper kidnapped Hinata, knocking her unconscious and chaining her over the edge of a roof. He then called Touya with Hinata's phone and told him about it. Touya asked if this had something to do with the Grimoire but Ripper said he forgot he was asked about that, only doing this because he found Touya interesting. Ripper told Touya he had to find them before sundown or he'd kill Hinata and hung up. After Touya ran into Kuon, he received another call from Ripper, who said he was tired of waiting and activated his Drive so Touya could follow the Discover Call to him. With the help of Kuon's magic, Touya reached Ripper and Hinata. Touya begged Ripper to let Hinata go but Ripper just made fun of him. Ripper told Touya that he had a strange “odor” similar to his own and Sechs's and he wanted to find out why that was for fun. In order to make Touya unleash his power, Ripper told him that he was the one who murdered Yuki's parents. When that didn't work Ripper cut the chain holding Hinata, leaving her to fall to her death. Touya went berserk, unleashing the power of the Origin of the Grimoire, which stole the seithr from Ripper's body, causing him to run off saying it was not fun anymore. A heavily weakened Ripper escaped to the sewers, where he was found by Avenge, who attacked him. Ripper claimed that he surrendered but tried to attack Avenge when he approached. However, Avenge saw this coming and countered his attack before killing Ripper. 
- XBlaze Code: Embryo, Episode 1
- XBlaze Code: Embryo, Episode 4
- XBlaze Code: Embryo, Es & Hinata Route Episode 8
|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 ·|
|Phase Shift||Ayami Yayoi ·|
|Crossover Characters (BBTAG)|
|Persona 4 Arena/
|Under Night In-Birth|