Musuko no Musuko wa Dare no Mono!? ~Musuko Soudatsu Haha Imouto Sensen~ / 息子のムスコは誰のモノ!? ～ムスコ争奪母妹戦線～

Since my father died suddenly of illness, I have moved to live with my mother. At first she was depressed and crying, and then she began to pester me with indecent proposals. My sister had previously lived in a school dormitory, and, worried, returned home. She, seeing our way of life with my mother, was shocked, and then very angry. My mother and I have become useless people to her. The sister tried desperately to convince the mother, and try to resolve the situation by depriving me of contact with my mother. Oh, what is this? Has it all slipped into such a funny situation? Maybe I have sex with her for the first time?
Under one roof, the battle for the son of a beautiful mother and daughter begins!