Imouto ga Ore no Koto Sukisugiru

As a result of spoiling his adorable younger sister Ono Natsuki, she has become a girl who absolutely adores her older brother. At home, she never leaves her brother’s side, and his lap is her favorite spot on the sofa. Even now, they bathe together, and even when their parents give them separate rooms, she still ends up sneaking into his bed. Their parents have now completely given up on seeing how close they are. —However, this endlessly sweet daily life is suddenly disrupted. The trigger was a “sex education” lesson Natsuki received at school.