Will you drown yourself in my love? Caresses all over my body, oozing wet deep inside... Should I really be doing this with somebody who's just a substitute boyfriend...!? One day, the man whom Yumina thought of as her boyfriend, suddenly tells her that he is going to marry another woman, and Yumina realizes that he had only been treating her as a fuck buddy. She's unable to talk back to him in the moment, but when she complains about it to her best friend at a cafe the next day, Aoyagi, a waiter at the cafe, butts in! He suggests being Yumina's substitute boyfriend until the wedding, in order to get back at her ex. Her body and soul are now at the mercy of the boy, who is friendly and approachable, but rather forceful during sex...