Kourtney and Travis are on yet another romantic Italian getaway, where she slipped into a black bikini and climbed on top of her man on the shores of the country's most famous lake.

It's the first time we've seen Kourtney and Travis in lovebird mode since their late-night Las Vegas "pretend" wedding ceremony earlier this month ... and now they're looking like honeymooners.

Travis was shirtless as he sat next to Kourtney on a couple of lounge chairs by the lake ... they talked for a bit, and then she couldn't resist and got all over him!!!

The couple, who are anything but shy, also grabbed a bite to eat ... and took pictures of each other on their balcony.

Kourtney and Travis just hit their Italian trifecta ... we've also seen them attached at the hip in Venice and a small town in Genoa.