Bella Hadid & Hailey Baldwin Butt Buddies ... On Land And Water

4/30/2018 7:21 AM PDT

Bella Hadid & Hailey Baldwin Hang Out, of Their Bikinis

Bella Hadid and Hailey Baldwin went sun's out, bums out while cruising around Miami on a luxury boat -- and got SUPER close once they got back on land.

Both ladies spent Sunday on "The Groot", the boat that belongs to nightclub owner David Grutman. Bella, Hailey and friends were hanging with Grutman and his wife ... when Bella decided to get real cheeky. She was definitely playing it up for the cameras, and showing everyone her weekend workouts are paying off. 

After docking, they kept up the touchy-feely fun, as Hailey worked her lap dance skills for Bella. Check out the pics. You'll be a big fan ... of friendship.