I got excited and hard while working out, unknowingly flexing my ass. The instructor noticed and, seizing the opportunity, showed off her voluptuous ass in tight leggings! My cock was rock hard, squeezed and rubbed between her fleshy cheeks at her whim! As my desire to penetrate reached its limit, she unexpectedly took me from behind into her ass! Skillfully controlling her external anal sphincter, she expertly tightened it for mind-blowing anal sex, making me ejaculate over and over again!
