Noctis is one those people take a while to wake - the sort who moan and and shuffle about aimly upon waking, completely unaware of their surrounding. Most days it just means needing someone to point him at the nearest sorce of caffeine, but some days, when he falls asleep naked (like just after a shower or sex) and well, its not like he's gonna be aware enough to put something on...
-Ignis being horrified and chasing Noctis with a bathrobe.
-Prompto getting blackmail/wanking material.
-Gladio just sitting back and enjoying the view.
- That one time Noctis streaked at a diplomatic brunch.
- Wandering naked into parking lot where they syayed in a caravan.
+++bonus point if this happens while they're with Ardyn