Aina, a Aina, comes to the guesthouse run by her father-in-law Yukio to visit her mother-in-law's grave. The natural hot springs and the abundant nature make her feel free in both body and Kokoro, as she grew up in the city... However, as Aina unconsciously exposes her youthful body, her father-in-law, who had long forgotten about women, is aroused by her lust... That night, unable to resist, he attacks Aina while she sleeps. Aina resists the intense caresses and thrusts, but feels pleasure. Her body is still throbbing even the next morning after being penetrated deep inside her vagina, and she cannot forget the pleasure...