Sixteen year old Syo lives in a normal city in Japan, or so he thought. When one night, when Syo walks home, he learns just what happens in the of his hometown's dark streets. Espically after meeting Unamo and Ittoki, a girl and boy who save him from a bandit. Turns out, the two belong to a group of assassins called the Shadow Hunters. Then, they offer him a job. Mainly because Shadow Hunters' sweetheart, a young girl named Ayame, says she "Sees his potential." But, is Syo ready to deal with eight murderous teens who run the streets at night?