G-Eazy Gets Handsy on Halsey's Butt in Miami

G-Eazy and Halsey, as a couple, are grabbing a lot of attention -- but he's just grabbing her ass.

The rapper and singer were spotted relaxing Monday in Miami, just a couple days after grinding all over each other during a performance at E11Even nightclub. They left little to the imagination here ... especially Halsey in her white bikini.

The "Him & I" duo weren't there alone -- a bunch of friends also joined them on a yacht, but G still wasn't shy about getting handsy with his girl.