Boku to Imouto

A brother lives a seemingly happy daily life with his younger sister and their school friend. The three of them spend their days together, sharing ordinary moments and having fun as a close-knit group.

However, the brother soon discovers that his sister's feelings for him go far beyond sibling affection. To make matters even more complicated, she is not just a horny girl but a futa, which turns their relationship into something far more explicit and unconventional.