One of these is small enough to hang on a string around your neck. They only have 2 shots and very little range but they would kill a raccoon or a large dog
https://bondarms.com/bond-arms-handguns/snake-slayer/
LOL! Good luck hitting a running target with that!
I have a .38 Derringer. It really hurts to fire it. I had to make special light loads for it. I can’t imagine how bad .357 would hurt.