Our pathfinder campaign has a goblin fire-bomb alchemist named Crashnark (Crash, for short) in it, who has a high fire resistance. So the party gets confronted by a gang of bandits.
Crash: (OOC) I use my free action to take a bottle of liquid fire and splash it on myself.
DM: Okay, but Crash isn’t wearing his fire-resistant clothing. All his clothes turn to ashes in seconds.
Crash: (IC) *Runs butt-naked and completely on fire at the bandits* CRASH’S BODY IS READYYYYYYYY!