A younger sister who takes a nap in front of her brother. Her unprotected appearance makes her brother start masturbating with lust even though he knows she is her sister. The naughty mischief against her sister who doesn't happen to her gradually escalates. But she is caught by her sister and pulled away. Even so, the gentle sister who can't hate her brother must have been pissed off because she's piling up, right? And offered to help with masturbation ...!
