In this adult role-play, my girlfriend's sister Riko has exactly the gorgeous ass I crave. While my girlfriend is away for work, I seize the chance to force Riko down and lick her ass. She resists at first, but my tongue and hard thrusting eventually make her twitch and cum repeatedly. Convinced that her pussy and my cock are perfectly matched, I pound her again and again in the living room, bathroom, and my girlfriend's bedroom, then tell her never to reveal our secret to her sister.