So there's two people, let's call them Fred and George, who are picking on one of our office mates - let's call him Ron.
To be fair, Ron does have some habits that are quite annoying for some people, like not being able to understand social cues - when to stop talking and bugging other people when they're busy with work, among other things. Fred and George also make fun of him sometimes because of things like being obese, or that he's still living with his mom (he's 40), or his overspending on the occasional travels saying that he doesn't know how to handle money.
For reference, Fred and George are about 30-40 years old. I'm 21.
I'm not directly in the bickering, but it makes things really awkward in the office. When I'm with Fred and George, they keep ranting about Ron's faults.
I tried to talk to Ron about this, so he could try to stop some of his annoying behavior (of course, I didn't word it like that), so that he wouldn't be the target of Fred and George's behavior, but he seems immature as well in his thinking. "Why would I be nice to people who are not nice to me?", he said. Fred and George shares the same mindset. This is an endless cycle.
I've had thoughts about leaving the office just because the environment is toxic.
It's also hard to bring it up to upper management, as the bickering and the tension is not evident enough in the general view. Only if you have inside knowledge of Fred, George, and Ron's relationship do you see the tension. But when you do know the background, you can see that a lot of their language is disguised as an attack to the other party.
As a fellow office mate, what is my role in this?
Edit : To be fair, I also talk with Fred and George so that whenever we're together and they talk about Ron in a bad manner, I try to defend Ron.