My niece suddenly shows up from Tokyo, asking to stay at my place because her mother's father—my late wife's father—has suddenly fallen ill. It's been a while since I last saw her, and she's grown far more than I expected. She keeps seducing me relentlessly, leaving me completely flustered. She's intensely curious about my cock, and as her uncle, I can't resist her advances. In this remote countryside, inside a run-down old house, a dreamlike seven-day sex marathon begins with my niece.