During the Valentine's season, Tomo shares a passionate and intimate first experience with his possessive girlfriend, Yuzuha, who surprises him with a unique chocolate-themed treat. Simultaneously, Shou and Masami's conversation about adult doujinshi sparks an unexpected sexual tension that leads them to experiment with their own desires.
Ryouta navigates a tense love triangle between his girlfriend Miu and gravure model Mika, which eventually culminates in a passionate threesome. Simultaneously, a mysterious girl named Alice arrives from another dimension, claiming to be Ryouta's former lover from a past life, leading to a steamy reunion and her sudden decision to move into the room next to his.