To me, a parody/satire isn’t the same thing as plagiarism or “ripping off” someone’s work. Done well, it’s an entirely new work. Surely, it plays off your ideas, but that’s not the same thing as stealing them. If someone copies your work, you’re owed restitution. If they simply poke fun at it, take it on the chin and don’t sue. At least, remember that you can always parody your own work. Some creators are unwittingly way ahead of themselves that way.