Crazy Bob.
He'd ride his rickety old bike around town at 3am mumbling nonsense to himself, and he grew corn in his attic that you could see through the windows. Iirc he was a war vet, so, y'know.. no-one really gave him any guff.
One summer though crazy bob was out rippin' around and apparently rode past a house party where a bunch of teens were in the garage drinking. I guess there was a fight outside, and as ole Bobby boy was rollin past he decided to JUMP IN AND FUCK EVERYONE UP. Lol.
From then on it was a running gag at any house party in my home town that there were to be no fights, because Crazy Bob would be lurking in the shadows waiting for his opportunity to strike, and no-one wanted that...