Yuya returns home for a long break from university. His heart begins to race again when he reunites with Rin, his mother's friend whom he has secretly admired for a long time. That night, he spends a sleepless night, nervously knowing that she will be staying over, when a drunk Rin visits his room... Unable to resist her defenseless and aggressive behavior, they end up having a relationship. Yuya is excited by this secret affair between the two of them, but Rin, who has been struggling with her husband and has sex with him as a way of getting back at him, worries that "this can't go on like this"...