Prompto would have smiled at Noctis' huff, then at Gladio at least still backing him up. But his mouth was a little busy, so he settled for a little mental smile. Noctis had so readily accepted him and he wasn't about to let that go to waste. His tongue immediately sought out Noctis' where it stroke and curled, enticing his to join.

The hand still on the back of the couch clenched the cushion a little harder as he felt Gladio lick down his back and place hands on his hips. He wanted to arch into the touch again when he felt Gladio nip his skin, but the hands prevented the movement. Still, he couldn't stop the muffle 'mmph' from being released into the kiss. He tried moving again, more into Gladio or something to show that he was kind of anticipating it now, even though it would mean the end of his kiss with Noctis when he really got into it.