Upton & Chmerkovskiy WHAT THE HELL Is Going On Here?

6/13/2013 12:15 AM PDT

Somebody's got some explaining to do ... because model Kate Upton and "Dancing with the Stars" pro Maksim Chmerkovskiy ... the most random two people ever ... left a restaurant together Monday night in NYC.

There were reports the two were spotted canoodling inside ... but sources close to both camps tell us, they're not together. Not even close. They're just friends.

Still, how are they even friends? This doesn't make sense.