Teasing and poking fun at someone can often be harmless: if everyone is good with the ribbing, few feelings suffer. This is why, when we're making new seating groups in class, I always ask "Who wants to get picked on this time?" I always have a lot of students to choose from to use as an example kid that one might not want to get stuck with. "We all know someone will get stuck with Bob," I begin, "But what is our reaction to being grouped with someone we're not crazy about?" "Nothing!" comes the chorus reply. Yet despite this there are still some moans and complaints about the groupings, though to their credit, the students are almost always complaining because they're with some of the same students they were with in the last seating arrangement. Sometimes, though, the ribbing and joking don't feel like jokes, especially when they're not the product of mutual consent. Yet some people knowingly, even intentionally, cross that line. They do annoying things because they are annoying, and the more we ask such a person to stop, the more likely they are to continue.

That type of mocking, non-consensual ribbing often has less to do with the target of the jokes than the joker: people do that to seem funny and draw attention to themselves. The fact that they seem to steamroll someone else is purely coincidental. They're not making fun of you; they're drawing attention to themselves. When we're the object of such silliness, we likely do better to ignore it or simply smile and agree with them: there's little you can do when someone agrees with you, and it slows or stops the momentum of the encounter immediately.

But what about people who continually harass? What about people who push it into bullying, which would entail the intent to hurt? Why do those people hurt others? The common answer is that they feel small and hurting others makes them feel big. Bullying, after all, definitionally entails a power imbalance, and for someone who's always felt on the light end of that imbalance, the chance become the agent of power might be too tempting to pass up. That's just a reformulation, I guess, of the truism that those abused sometimes become abusers themselves.