OK, I put a lot of thought into this, and here's what I've concluded.
When the girls came up to anon and suggested the bet, he should have said: "Sorry, ladies, I can't take that bet. See, whenever I do something, I give it 100%. So when I'm on the court, I'm being true and faithful to the sport of basketball. And the one thing I can't do..." (he locks eyes with the girl he likes) "...the ONE thing I can't do is be unfaithful." (he gives his best boyish grin, then goes and makes the dunk.)