Freeter Yamada, who only thinks about butts, had his niece Nanami staying over. Nanami doesn't listen to anyone and plays games all day long. She carelessly exposes her beautiful butt... Yamada can't hold back and buries his face in Nanami's butt... At first, she is surprised by the sudden act, but soon starts to enjoy it and even begins to tease him, demanding more... Their secret relationship began that day.
