Okay I know this is tmi

Melody
I know this is tmi, but I really need opinions, so my boyfriend and I had sex today and yesterday and when we had sex after wards he notices looked like white cottage cheese on him, I cleaned it off and it looked like toilet
Paper, and it literally only happens when we have sex, I'm not itchy so I don't think it's a yeast infection but then again I don't clean up right away after he cums inside me with no protection. What could it be? Should I be worried?