Chisato and Mahiro are two high school girls who are about to graduate. They also happen to both be highly skilled assassins. When the organization they work for orders them to share a room, the relationship between the pair quickly turns sour. However, when they find themselves targeted by the yakuza, the girls quickly realise that they will have to find a way to work together.

Chisato and Mahiro must pay four years of overdue fees or lose their membership in their assassin guild. They take part-time jobs, but find themselves in the middle of an armed robbery and being hunted by other assassins.

Teenage assassins Mahiro and Chisato visit the coastal city of Miyazaki for a contract and a vacation when they unexpectedly cross paths with a legendary, bloodthirsty assassin who's looking to add to his kill count.