With Imouto...

"My cute little sister Yukano took a walk with some boy!?
As her older brother I have to do something..."

Caress and command into the panties of your sister, resulting in intercourse and a cummy inside finish.
Progression is Prologue, Game screen, Penetration, with 4 different endings based on your choices.

オレの可愛い妹・由香乃が、男子と一緒に歩いていた!?
これは兄として、問いただす必要がありそうだ…。