My younger sister Yui, who is a little older than me, has been a spoiled brat ever since she was a child, sneaking into my futon. But one day, Yui brought my junior colleague over as her boyfriend. When the three of us slept in the same room, the voices coming from the futon next to me were not happy, but rather hot and sexy... "What on earth are you doing in futon...!" We secretly pet each other in the bathroom, secretly cum inside her brother's futon, and have intimate, intimate creampie sex. The doted little sister writhes quietly next to her brother.