Signed, Sealed, Mistaken

An introverted high school student, Souichi Sakuraba, is bullied severely by the “Yokai” classmates. The bullying escalates, and Souichi’s childhood friend, Azusa, who was the only one who trusted him, is defiled by them. In front of Souichi, who was in the depths of despair, the succubus, Asmode, appeared. Souichi makes a contract with a succubus who possesses a mysterious ability and decides to make the bully’s loved ones suffer the same pain as himself by “cuckolding” them. The obscene revenge by “NTR” begins.

A fateful mix-up brings an unexpected twist to a student’s life at a cram school. When a mysterious package meant for his star lecturer, who shares his name, lands in his hands, an unusual relationship begins to unfold between them—one that blurs the lines between student and teacher.