Blac Chyna & Rob Kardashian: Lick It ... Lick It Good!

Rob Kardashian got a faceful of DNA on his way out of a laser skin treatment center ... courtesy of Blac Chyna.

BC gave her man a good ole fashion tongue bath outside the Epione Cosmetic Laser Center on Thursday evening -- a far more romantic display than the platonic one posted on IG a few hours earlier.

Now that we see the actual swapping of spit up close ... kinda sorry we questioned their passion. We get it guys ... you're really dating.

#ewww