My niece, Rina-chan, came to stay at Yamada's house, a freeter who only thinks about her butt. Rina-chan doesn't even listen to people, she just plays games all day long. Surina-chan exposes her beautiful butt defenselessly. Yamada can't stand it and buries his face in Zurina's ass... Although I was surprised at the sudden act at first, it became fun from the middle and on the contrary I asked for more and more as if playing with my uncle. From that day on, the secret relationship between the two began.