I get a lot of horrible thoughts, mainly about animal abuse from OCD.
For example, I used to have a gas heater and would imagine putting my snails on the grates which traumatized me quite a bit, since I would never in a million years do something like that.
I also get thoughts about murdering people, mainly though I'm always thinking of the near impossible "perfect murder", which has to do with my serial killer fetish.
If you think you could seriously hurt someone, though, I would suggest professional help.