FNS-161 The Mischievous Little Sister: Amanatsu Yui

At my sister's birthday party, I accidentally stared at her panties... Thinking she despised me, I tried to keep my distance at home, but for some reason, my sister Yui clung to me and, defenseless, spread her legs in front of me, showing me her panties. Her plump buttocks and healthy thighs showed signs of growth. Whether she knew how excited I was about someone I shouldn't be attracted to or not, Yui brought her crotch even closer to my face...