Taking down dictators and assassinating crime lord, now that's the easy part. Junior High, now that's the hard part. No one knows this better then Ryoma Erchizen. Being an assassin and an unwilling tennis prodigy isn't something that Ryoma does easily. The fact that his boss is a sadistic bastard doesn't really help. Now Ryoma is assigned to Tokyo. Not that he minds...until he finds out where he'll be going to school at. Seishun Academy. To top it off, a certain someone, from Ryoma's dark past, decides to appear in his life again.

When Saiko, an insane fifteen year old boy meets his shy new neighbor Usagi. The two form a bond over the course of three years. From burning down a school, killing college, and almost beating his class mate to death. Saiko will do anything to protect his little rabbit. But when a curse awakens, he finds out who he truly is.

Ten years ago, a mysterious special area known as "Hell's Gate" appeared in Tokyo, altering the sky, damaging the area and making it inhabitable. The real stars disappeared and were replaced with false stars. With the gate and fake stars came Contractors, human's with supernatural abilities, each one had a corresponding star that reacts with their abilities. The Contractor's were kept secret from most of the human race and are known as "Brutal Killers" to the few humans that do know. Contractor's have no emotions and they each have a distinct price they pay for using their abilities. Organization's like the MI6 use Contractors as spies and assassins resulting in violent acts. KS306, also known as Kaede is a Contractor and works for no one. The Syndicate is after her and will stop at nothing to get their hands on her dead or alive. What will happen when they send their most skilled Assassin BK201 to bring her back?

One person, one knife. That bloody night, the village of Tsukiyomi clan, the strongest clan. Was massacred by no other than their pride, the Tsukiyomi princess. Jigoku Tsukiyomi, the princess of the twin moon clan. Was once the angle and guardian of Tsukiyomi, but she lost her wings, fallen and into the deepest of hell. She has lost her way, walking further and further from the right path. "No one can help, no one can save me......." Was what she thought. Until the day where her guardian angel found her, saved her, took her to the right path and pulled her out of hell. There is now a chance for her to be an angel again, but will she take the offer? Only she will know............