That's the kind of slutty sister every brother would let work his testicles. And this one probably accustomed her to these pranks a long time ago. At least that's what I would have done. She'd have to suck and spread her legs anyway, so why not with her own man? It's about time she got her ass printed, too, so she can date like a grown-up bitch. Or maybe she's still trying to keep her anal virginity for her husband.
I love flexible female athletes, with whom else can you try interesting sex positions from Kama Sutra? The man is very lucky, I think he will meet this lady more than once in an intimate setting. You won't be able to forget such a woman, because they are so rare these days!