Incest [silent] Incest - my dad is next to me...

It's been four years since I remarried my current husband. Yukari was troubled by her stepchild Kosuke's relationship with her husband. He also practiced acting as if to be aware of his stepmother as a woman, and his underwear was stolen while taking a bath, so these suspicions continued to grow. One day, when he enters Kosuke's room, he witnesses Kosuke trying to masturbate in Yukari's underwear. Yukari questioned him, but on the other hand, he was attacked by Kosuke...