I was at a meal. One of the guys there was another musician, a keyboard player. He was extremely annoying and clearly thought of himself as a big deal. (SPOILER: He was not a big deal)
Partway through the meal, he leans across me to (clearly) try to chat up the woman opposite me. I say (slightly sarcastically) "Oh I'll just get out of your way then", at which point, he puts his hand on my thigh to intimidate me, to which my reply, in a sweet and reasonable voice, is "Move it or lose it". He moves it.
He spends the rest of the evening being annoying, and as we part, he says to me "You're a very challenging individual". I say nothing, but I am of course thinking "Yeah, and you're a **** too, mate".
He didn't come to the group meals again, and me and my friends laughed from time to time about how annoying he was, in his "I am a big shot" way.
I performed no magic against him at any time.
Fast forward a few years. I am at the group meal again, and the guy who runs it says to us "Did you hear about X?" X being the annoying guy. He then tells us that X caught necrotising fasciitis somehow, and lost all the fingers on his left hand. The same hand that he put on my thigh.