Born to the Amanohokosaka Clan, Tenjo became the Imperator at a young age, and took on two students - Kagura Mutsuki and Bang Shishigami, with both becoming members of her personal guard. During one meeting with nobles, Tenjo grew sick of it, and decided to walk into the gardens of the household to relax. There, she met Meifang Lapislazuli, the child of the lesser noble family. Kagura interrupted them, and Tenjo punched him over the head for being rude to her guest - Houichirou Hazuki did the same, and carried him away. Over the years, both Tenjo and Meifang grew close as they would sometimes spend days walking through gardens.  The details are unknown, but the body Tenjo was in was a vessel she was possessing. At some point, she met a man with brown hair and they had a child together - Homura Amanohokosaka. She would regularly have meetings with the Duodecim.
In the Ikaruga Civil War, a coup d'etat was performed that removed Tenjo from her seat of power by Hazama, Yuuki Terumi, and Relius Clover. She formed the Ikaruga Federation, created an alliance with Sector Seven and the NOL declared war against her. At one point, they were winning the war, but Tenjo had wished to end the war without casualty; the Committee pressured for the war to continue, and she was forced to. Rumours had circulated at this time that she wore a mask to hide a huge scar over her face.
Ikaruga Civil War
She had planned to transfer her soul into the Nox Nyctores - Deus Machina: Nirvana, but Relius stole it, and she was unable to do so. She went down to the basement of the Wadatsumi Castle and looked at the Kushinada's Lynchpin and Phoenix: Rettenjo, taking the latter as she knew it was the last thing she could transfer her soul into, even if it meant living a life where she could not feel - anything. Tenjo transferred her soul, but remained in control of her former body, carrying herself out of the area. 
Later on, Tenjo would give the Rettenjo, with her soul inside, to Bang, and issued for her ninjas to evacuate the castle, but Bang stayed by his mistresses' side. Jin Kisaragi stormed the castle using the Mucro Algesco: Yukianesa, and fought Bang, leaving him permanently scarred, and froze the entire room using his Arctic Dungeon technique. Tenjo talked to Jin while Bang screamed for her to escape, but she stayed, and asked him to kill her and to fight against the "death" that will be born. She threw a charm at him, baiting him to kill her - Jin used his Yukikaze technique and killed Tenjo's old body. Jin's memories were erased by Terumi, and Tenjo's old body was replaced by someone with a large scar on their face to match the rumours. 
After the war had ended, Meifang desperately clung to the dream of making conflict extinct, all in remembrance of Tenjo's ideals; this would be done by making a Nox Nyctores. In her final moments, she saw a vision of Tenjo, and confessed that her true dreams were to just be by her side. 
Bang finally came to realise that Tenjo's soul lay inside the Rettenjo he had been gifted years earlier. Rachel Alucard came to the realisation that there was another way to activate the Lynchpin without using Celica A. Mercury's soul as the catalyst. Tenjo's soul was used instead, and the Rettenjo was hammered into the Lynchpin, stopping the flow of seithr.
Tenjo's soul was still anchored inside the Lynchpin inside the Embryo. Ragna the Bloodedge took Tenjo's dream using his Soul Eater, and promised her that he would look after the people of Ikaruga, Bang, and most importantly, Homura.
- BlazBlue: Variable Heart, Chapter 14
- BlazBlue: Spiral Shift - Hero of the Frozen Blade, Chapter 4
- BlazBlue: Spiral Shift - Hero of the Frozen Blade, Chapter 6
- BlazBlue: Variable Heart, Chapter 18