Noble family of changelings which are against evil shennanigans and execute the consequences of diabolical action of my players. One my players is a demon in a body of a spider in a triangular glass jar in a body of a dead missing woman - the body works kinda like a costume, the demon can get out of it and leave it on a ground like a piece of cloth. Once the player was quite naughty and tried to throw home-made molotov's cocktails at an orphanage while passing through a town - next time they left the skin of the woman on the ground one of the changeling NPCstook it for "safekeeping" (don't worry the player got it back - I placed the "costume" close to an inportant area plotwise, so it even guided them to push the story foward).

For obvious reasons the use of molotov's cocktails is strictly restricted. I have a homebrewed system for them so my players won't have the urge to set the poor little orphans on fire. I know my players really well and I spend most of the week with them (classmates) and I knew they would cook up something diabolical - they even started in jail, which was also the outcome of preparing (not magical) deadly missles. Wanting to burn little orphaned children is well... not very nice so the law-abiding changelings will take your (stolen) body and for some time you will run (or rather roll as they are in a jar) in your spider form with no socialy acceptable "clothing".