Mizuse Chiho

Humans are always evolving. The ones who evolved in the right path would embody superpower, and called the "White." However, the when their psyche can't keep up with the evolution of their body, they'll lose their mind and go berserk. They are called the "Black." Jin is a part of Black Line; the security company against the Black. Jin swears to eliminate all the "Black" from this world–– weather by finding a cure to end the spread of the "Black," or with his own fist and power.

Eyama Aito, a high school student, is the victim of daily bullying. One day a strange letter arrives inviting him to a "captivity game." He may choose one person to hold captive for one month with a chance at winning a large amount of money. He chooses the ringleader of his bullies, Aya Kirishima, and the only rule of the game is to not kill her. Everything else is fair game. Eyama's revenge begins!