JUFD-916 A defenseless big-breasted sister gets fucked by her super-obsessed younger brother. She thought she was trying to seduce her virgin brother, but... it turns out to be a complete reversal! - Mio Kimishima

Mio, who was working as a model in Tokyo, returns home for the first time in a while. - Her parents are happy to be back together after a long time, but her younger brother Jun seems to be stuck at home instead of going to school. - In that case, he teases, ``If you go to school, I'll let you fondle your breasts...'', but this awakens the younger brother's dormant sexual desire, and his big breasts are roughly rubbed and he cums in a childish sex. - From that day forward, he will be chased around all the time by his unfaithful younger brother...