Posing as uninterested in men, their college friend, Kasuki, got close to Mayu and even convinced her to become roommates. However, when he found out Mayu had a boyfriend, he flew into a rage, vowing to make her regret their living arrangement. "This body is mine!" he declared, grabbing her ample ass and G-cup breasts, then unleashing his pent-up semen onto her body, letting his suppressed desires explode. Despite Kasuki's persistent advances, Mayu tries to make him give up by showing him her intense sex with her boyfriend right in front of him...