如月 佑

Yuu is the younger brother of Maaya. All his schoolmates said his older sister is a kind and beautiful girl with amazing oppais. He actually thinks the same thing and actually thinks his sister is the cutest girl in the world. He doesn't like his friends looking at his sister's breasts and at times he becomes very protective.

They have always been very close and Maaya has always been very kind to him. They used to absolutely do everything together, even bathing. But the actions of his sister trouble him more and more because she exposes herself more and more. Currently, not only he found her very pretty but also very erotic. He is completely fascinated by his sister.

Recently, and because of his friend's eromanga, he began to fantasize about Maaya while masturbating. But Maaya caught him in the act because he was moaning loudly while saying "onee-chan" and she asked him who he was calling while he was relieving himself, the magazine's onee-chan or she, Maaya-nee.

And this event marked the beginning of their story.