machi, who loves her boyfriend but somehow the timing is bad and they haven't had sex yet. she thinks that someday, but she just can't bring herself to do it. one day, she meets her boyfriend's brother, who has a slightly bad vibe. contrary to his appearance, her boyfriend's brother is kind and gives machi, who has a headache, a headache medicine... when she realizes it, machi is restrained. machi, who is given a love potion by her boyfriend's brother, is driven wild by unknown pleasure. before she knows it, she becomes a creampie meat toilet.