Ignis doesn't have a chance to get to 'just do it' territory. Gladio actually pulls back a little and for a moment he's pleased that Iggy can't see the wicked grin on his face. Oh? Oh it's out of respect for Prompto's virtue?

Hell no.

Gladio does wait until they get to the cottage at least, dragging Ignis inside and slamming the door behind him, shoving the advisor back against the wood and immediately plying his mouth to his throat again. Teeth catch over his pulse, biting down firmly, sucking gently at the spot then laving his tongue over the forming bruise only to start sucking again. Each breath reverberates in his chest, rumbling out of him in a soft growl against Iggy's throat as he bodily pushes him up against the door.