haha I'm sure they have seen it all, and an problem doesn't look any prettier hairless or not. Just go as you are and hope it gets over with quickly

Trimming ass? Wouldn't that get very itchy when the stubble starts growing?

no, don't. They don't get their faces right down there, anyways, so it's not like they'd notice. Besides, if you trim the hair too short, you could get a rash from ingrown hair/stubble and it could attract more attention than needed.

Just make sure you're clean and you're good to go.