I crave Prompto being dressed up in expensive chains, collars, and clothing being forced into uncomfortable situations. Perching on people's laps during banquets or meetings, passed around like an object.

Maybe Prompto is a spoil of war? Or an unwilling gift from one nation to another.

Given as a reward to the kingsglaive to use for the night? To Prince Noctis for coming of age? Kept by Regis as a bed warmer?

ANYTHING GOES! his owner(s) can be sympathetic to terrified prompto or keen to show the boy his new place. All up to anon!