Your sister was a sexy yoga instructor. She had an amazing body: long and slender legs, a small but firm and round ass, nice tits, which she never covered during yoga. She pretended like nothing happened, but you were paying attention. By the way, not only you, but also your dick, which was getting harder at every practice....Sister saw it and smirked innocently. She had some very dirty thoughts in her head, but she couldn't give in to lust and give in to desire, so she just teased you with her body....Someday it would end in something very hot