After Sota takes his wife to the station for a trip, he struggles with housework during his rare time alone. His wife’s older sister, Yuria, suddenly arrives to help. He enjoys her cooking but cannot stop staring at the thick breasts in front of him. He survives dinner and retreats to the bathroom, only for Yuria to follow him inside. Faced with the naked breasts he has always forced himself not to look at, Sota’s cock swells to the verge of exploding as a two-day, one-night seduction begins.