HUNTB-682 1-day limited taboo incest! "Big brother, are you excited because of me?" "You're excited because of me too, aren't you?!" My little sister's unintentional seduction makes my virgin self hard

My younger sister has recently grown into an adult-like body. When I looked at the casual panty shot and the guard's sweet chest, I couldn't help but get an erection! Then he said, ``Brother, maybe it was me who got you excited? '' and she couldn't help but think, ``You're excited about me too!'' ” to the situation where he retorts! It is true that I, a virgin, had an erection. But her sister was her sister and seemed excited by my erection... In the end, the ugly argument crosses a line that should never be crossed... They both think it's just incest for one day.