The Unwanted.

At 18 years of age, everyone gets a weapon based on their personality and strengths. Everyone got a traditional weapon, but Hakru Gin?
He got something interesting that no one knows how to wield.

Hakru is an outsider, a freak, a weirdo, an unwanted.
Hakru lives a poor life, he has middle-class parents who hate him and think he's useless, everyone at his school thinks he's a lame freak for the way he acts, his teachers pick on him more than anyone else. Everyone treats Hakru like trash, everyone except Ayuko Wakame, Hakru's only friend. She's a middle-class A+ student, she would be one of the "popular girls." if she didn't stick up for Hakru.
These two teens have no idea about what will happen on Hakru's 18th birthday, but it will change them forever.