Most guys know even if had not told him.
and then there is the occasional relationship that could have
started here. And if he did know...who can say if he wasn't at the place just 10 minutes before you walked thru the door and filled her honey box with his love juice before you went down on her? or maybe she took his loving load in her mouth before engaging in dfk with you? is that funny too or just wierd?
All I am saying is don't overthink the hobby.