The bite has exactly the reaction Gladio wants, scenting the release of that heat, feeling John's body uncoil beneath his. He gives it an encouraging nose, enjoying the sound of submission/desire/need/anger all in John's voice. There's something deeply satisfying about hearing it and it provokes a huff of a laugh out of Gladio to hear it. "I was careful," he informs the other. "Know how? I didn't rip them."

They could both be jackasses in their own way.

One thing John will learn quickly is pain doesn't bother Gladio. Most Sentinels had that in them when they were in a combat or Bond rage, almost Berserkers, but Gladio is someone who's trained from the time he was old enough to hold a practice sword to take blows, to go past the pain and thinking little of it until the job's done. On top of that... he likes it. Maybe it's tied into his personal love of the fight, but the pain makes him feel alive. So he'll stretch out under it, grunt at the flick but he'll give back with a nip of his teeth... though he's kind enough to move his mouth to John's jaw.