Fucking a yoga student while she's away

Vince Karter is having sex with Billie Star in the gym. He asks her out for drinks later but she has a better idea. She started sucking his penis right at the gym. They're doing it when a busty trainer, Tina Fire, peeps at them from across the gym, getting hot and horny while she watches. Tina decides to toy with the couple a bit before inviting them into the bathroom for a steamy and wild threesome.
Good movie here: