"I just want you to relax while I give you a back massage. It's just an old man's request. You don't have to listen, but..." Koharu Shiina finds herself in an unexpected situation as her usually quiet father-in-law makes a bold move. Unable to resist, she's gradually pushed to the corner of the bathroom. As her beautiful breasts are grabbed, the gears of their father-daughter relationship start to grind in an unpleasant way.