A friend is a retired fire fighter. His sister-in-law married an arsonist. Must have been some uncomfortable family get togethers!
I read a book about arsonists when the neighborhood I was living in seemed to have one.
Apparently, the type of arsonist classified as a ‘pyromaniac’ often returns to the fire or even calls emergency himself, to take voyeuristic pleasure in what he has done. Also, sometimes it is a first responder himself who sets a fire, in order to help put it out and appear ‘heroic’. A very strange psychology.
We had a firefighter in a company in the town adjacent to ours who WAS an arsonist. Instead of arresting him and giving him jail time, they quietly fired him. We wanted to hang him.
I'd have thought they'd get along like a house on fire.