What happens in Vegas doesn't always stay in Vegas -- especially if you are Prince Harry.

Friday night, Harry and his friends allegedly rolled out of their "high rollers hotel suite" and went to the hotel's bar, where they made some friends, which they invited up to the room to play a game of strip billiards.

One of the partygoers snapped a phone pic of Harry's bare bottom, which TMZ snagged for a pretty penny. Luckily, the photo editors put a nice red star over his butthole. (I don't think we could have taken much more regal nudeness this early in the morning.)

Well, at least we've all learned two very important things from this.

Underneath it all, Prince Harry isn't so, well, hairy. And, just because you're a royal it doesn't mean you are good at everything -- especially pool.

It's OK, Harry. We've all been there.

DiD yOu KnOw? ... Prince Harry also had some fun in a swimming pool during his stay in Las Vegas. Check out the pic, above, and the video, here. We wonder what his not-so-serious girlfriend/friend, Cressida Bonas, has to say about this? 

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