verb. (to black widow someone)
To break up with a guy right after he orgasms during sex. This is the point where a guy is the absolute most sensitive and is the most likely be the most hurt by it. (This is assuming you are already having sex with him.)
Jess: "I think I'm going to break up with my boyfriend tonight"
Julia: "Hey, you should black widow that douche nozzle!"
Jess: "Yeah, I bet he'll cry if I break up with him right after sex"