Cum stained underwear on show at the gym

So I'm at the uni gym this evening and this 20-ish fit-looking guy takes off his workout shorts in the locker room and walks past me in his dark blue boxer briefs. I'm checking out how his tackle is swinging when he gets on the scales to weigh himself. Now he's standing still I see he has cum stains down the side of his boxers, like he's wiped his hand there after jacking off! Wonder whether he knew what made me start smiling! :wink:

Anyone here seen anything like this? Did you say anything?