Cat\bf poop on sheets ???

So this is gonna sound crazy..but bare with me. Im not trying to be gross and i dont want to be rude to anyone.

I have a cat, ive always had cats. But has your cat ever sat on your bed and left a little poo or something ??

Because I've found little pea sized reminants on my bed/sheets twice but I honestly don't know if it's my cat or boyfriend ?

The first time it happened i thought it some how happened durring sex so I didn't say anything.

After we have sex I try to encourage him to clean himself (ill even bring him a warm rag) but he usually just wipes everthing on his shorts and gets back dressed ?

If its not the cat how do you address it??

..i think I'm gonna start locking my cat out of my room and see if that helps.o