Sera Rokudou is a senior student from the Aimafuchi High School in Adachi-ku, Tokyo. She is a strange, docile girl who rarely speaks. She is found by Aoi Misato on the streets at night, being groped by an older man; showing no emotion, Sera simply wanders off after Aoi saves her.

However, they soon discover that Sera is the one behind recent mutilations, and she is actually infused with the same supernatural powers. Her energy manifests itself through slash scars on her wrists, which send garret-like strings of power flashing out and slicing anything in the vicinity. She seems crazy and excited when using her powers, but she is not in control of it. During their battle, she starts transforming into a demon, and the Magami kids are forced to kill her. But she's saved again by Aoi, who shows strong signs of having an odd healing power...

Afterwards, Sera loses her memory, and ends up living on the streets; although she still has power, she is no longer a threat, nor harbors any ill-will. She's befriended by a group of homeless men, including Alan Claude.