Since his wife went home to her parents for the birth, Daisuke has been living like a slob. Her older sister Chiho suddenly arrives to handle the housework, and he gladly welcomes the help. But every time she cleans, he catches a glimpse beneath her skirt and stares at her tempting thighs. As the carefree Chiho presses close with a sweet smile, the last of his self-control begins to vanish...