Ageha wo Ou Monotachi

A woman named Ageha Shiraishi is imprisoned and awaiting execution for the alleged murder of her four roommates. She insists to her warden, Kyousuke, that she is innocent. Kyousuke investigates but initially concludes she is guilty. He later returns to find his superior restrained and undressed. After releasing her, he discovers he has been deceived—Ageha had impersonated her superior. Ageha has the ability to mimic others with perfect accuracy, including appearance, behavior, and voice. She escapes from Talsis Prison and announces her intent to uncover the true murderer. Kyousuke’s only lead is the swallowtail butterfly tattoo on her back. A pursuit ensues as the characters seek the truth.