Attention Tara Reid -- we now interrupt your Mexican vacay for shots of your BF caressing a tremendous bikini-clad ass ... that is NOT yours!
Not that Tara needed us to tell her, but yeah ... her dude, Yavuz Cansiz, shared a nice tight embrace with a female friend in Cancun while Tara got a bird's-eye view of the action.
As you'd expect, Yavuz had some 'splaining to do.
The last time Tara had this look on her face ... Kim Kardashian and Paris Hilton's asses were cruising by her.
8:30 AM PST -- Tara tells us the photos are misleading, since Yavuz isn't even her BF. Soooo ... grab all the ass ya want, dude!