MIDA-488 · I Was Tempted by My Girlfriend's Cunning, Erotic Big-Breasted Younger Sister and Fell Into Depravity

my girlfriend has absolutely no interest in sex. i thought i'd be able to bang at her house this weekend... i guess it'll just be watching movies and playing games... then, her younger sister, who is the complete opposite of her, comes home. my eyes go to yuuka, who is bending forward and sending wind into her blouse with a fan. then i get caught taking evidence of me staring directly at her tits, and since then, i've been spending all my time having erotic acts with my younger sister, betraying her...