18+ Fuuki Iinchou Seira: Anata Nante Daikirai, Shineba Ii no ni

Akihiro has no parents.... One day, he starts living at Serina's house. She is actually the principal of her school and forces him to have sex with her.... Two years later, a woman, Mirei, appears in front of him.... She is a younger sister of his father and tells him that all the property his grandfather left has been given to him. Akihiro soon plans to take revenge on Serina, but he accepts Serina's offer that he can own the Saotome sisters, Seira and Juria. He isn't actually interested in women, but Seira is the exception....

(Source: ErogeShop)