Marine, who’s loved to fantasize since she was young, is now a student and a popular erotic comic writer. Her happiest moment is when she goes into an erotic fantasy while writing a story. One day, Tomomi, her best friend, calls to tell her that she’s broken up with Yoshio, a senior student in the swimming team. Having had feelings for him, Marine wrote her debut story about a man modeled after him. Her editor, Eto, suggests that her stories have become too mannered. Is what stimulates her fantasy running out? In the meantime, Marine receives a strange aphrodisiac from Yoshio. What change will it bring to her when she takes it?