Scent of Seductive Flesh

Takuya is a university student in his final year. - He wants to earn some money so that he can go on a graduation trip with his girlfriend, Yuki. - He starts working as a live-in home tutor for Otoha Misawa at the Misawas' house. - One day, he finds a hole in the wall in his room. He looks into it and sees Kaori, Otoha's mother, doing her hair. - It seems he can peek into Otoha's parents' bedroom through this hole. - Who made this hole? And what is it for?​