The main character, "Ako Yamada," is a former skilled assassin. She now hides her true identity and works at a small bakery in town. However, Ako, who is ruthless and never fails in her killing missions, is actually a clumsy. Meanwhile, a high school girl "Nono Morino," an urban legend enthusiast, hears a rumor that an assassin is hiding out in town and comes to find out the truth. Ako, who wants to have a friend, and Nono, who is very curious, become friends, but Nono gets involved in a case.