That's gross, okay for their own home, but not outside of it
I'd take it back to him and not care if he felt embarrassed - he shouldn't do embarrassing things then
Spit in the sink - show it to him, show him where cleaning stuff is, get him to clean it up. 'I'm not your wife - I'm not cleaning up your spit, Bob, ha ha'.
Unflushed loo, just flush it if you find it.
Catching him leaving the bathroom - I didn't hear a flush, Bob, is there a problem with the handle? No? Could you flush it then please.
Non hand washers - on a couple of occasions this has happened to me, I go all out to embarrass them. Also, a lot of men oddly think that they didn't get wee on their hands, no need to wash them. Ah Bob, did you wash your hands okay, is that soap okay for you? You say didn't need to? Yes you do please. You are right that you probably didn't get any wee on them, but you were touching your cock and I don't want you touching things in the house with cocky hands, thank you. After all, I don't touch my fanny and then go round touching the doorknobs and stuff straight afterwards, ha ha. That wouldn't be very nice for other people, would it.' Getting that blunt has always shocked them rather and I think cured them of it in my home. Repeat offense 'ah there you go again Bob, please don't touch my sofa with cocky hands, please wash them.'
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