AppearanceShe has black hair. In the beginning and dress like a nurse.
In her true form, she wore a revealing battle armor and wields the Tomoe emblem and a Naginata. Her hair also grew significantly longer.
PersonalityShe was introduced being loyal and submissive to Saishi, however, Saisei fights to feel alive and for the man she loves, Shinrei.
She secretly fell in love with Shinrei when the latter spoke to her tenderly (something she didn't expect as the others treated her like an object). Since then, Saisei dedicated her life in protecting him.
They first met Demon Eyes Kyo and his group at Jigokumon, in Aokigahara Forest. Here, Saisei used Spiritual Surgery on Yuya to manipulate Shinrei's dragon inside her. So it remains only 12 hours to Yuya before the dragon devours her hearth. Later they encounter Kyo and his group at the second Goyosei's gate and fight against Akira.
DeathSaisei was killed by Akira after he defeated her ability to warp damage to her opponent, but he respected her since she was fighting so hard to protect Shinrei, whom she secretly loved
Abilities/ Notable AttacksSaisei uses a naginata to fight.
- Syringes and scalpels
Saisei's specialty. She can make her hands phase through matter and can perform surgeries on people without touching their skin. She used this ability to manipulate Shinrei's water dragon inside Yuya's body
- True Form
She can trasform to increase her combat stats
Saisei performed spiritual surgery on herself and transformed her cell structure into a sub-dimension. Every time someone attacks her, she can turn those attacks back on the sender. The downside of the technique that it works even in reverse. If Saisei's opponent stabs himself, they stab Saisei instead. To avoid this, Saisei constantly opens and closes the gate. When she attacks, the gate closes. When she defends, she opens up the gate. Unless someone catches her rhythm, there's no way to abuse this weakness.
Saisei spins her Naginata and generates a spiraling wind with swarms of sharp cherry petals to overwhelm her foe.