To prepare for the upcoming university entrance exam, Yuji has moved in with his uncle in the city. His uncle's wife, Ai, graduated from a prestigious university. Not only that, but Ai also possesses the elegant beauty of a city woman. That night, after finishing his shower, Yuji accidentally discovered Ai masturbating in the room. Ai noticed him and looked at him, but contrary to Yuji's thoughts, she smiled at him. The next day, while tutoring Yuji, Ai continuously revealed her seductive underwear. How could a young man in the prime of his youth resist Ai's beauty?! And for an entire month, the two engaged in a secret affair right at home, even when Yuji's uncle was right next to them...