Yayoi-san was the wife of the protagonist's older brother, who died five years ago. The main character, left in her care, grew up and began to pay close attention to her sister-in-law's sexy body. The girl, experiencing sexual hunger, did not fail to notice this increased interest and gladly gave the young man a new, life experience, but they were not destined to drown in the carefree happiness of pleasure for a long time...