Senior high schooler Hikaru Umino is desperately in love with his teacher, Kuniaki Shima. When he hears a rumor that Shima is engaged to be married, Hikaru does the unthinkable and forces himself on his teacher. Shima makes him atone for his sin by, unexpectedly, becoming “make-believe” lovers until Hikaru graduates high school. When the time limit expires, can Hikaru let go of his beloved teacher?
Light novel is based on this manga.