Rika, a girl with beautiful breasts who grew up in Tokyo, is visiting her paternal hometown. One day, Rika sees her uncle sleeping on the veranda. His crotch is erect due to a simple physiological phenomenon. Rika, who has no sexual knowledge, is curious and touches his crotch out of curiosity, Kokoro making him ejaculate. Before she knows it, her uncle has woken up and noticed. Since then, the perception that "Rika is a naughty girl" has spread among her uncles, and Rika has become the target of middle-aged men...