delericho
Legend
I'm another advocate of discussing acceptable behaviours in Session Zero. Thereafter, anything* that falls within the agreed boundaries is fair game, and has logical consequences. Stepping across the lines that have been agreed isn't allowed - if the party agrees "no PvP", then your character can't do it. Sorry.
* With the obvious exception that if we stumble upon some real-world trauma, or even simply discomfort, then we need to stop immediately.
One other thing: I no longer allow secret actions at my table. The player characters are the protagonists of the story, but the players are also the audience. So if you want your rogue to steal from his buddy the fighter, you have to declare that action out loud in front of the group. (The player of the fighter, who is oblivious to all of this, is expected to act accordingly.) I've found that doing that cuts out pretty much all of the worst behaviours.
* With the obvious exception that if we stumble upon some real-world trauma, or even simply discomfort, then we need to stop immediately.
One other thing: I no longer allow secret actions at my table. The player characters are the protagonists of the story, but the players are also the audience. So if you want your rogue to steal from his buddy the fighter, you have to declare that action out loud in front of the group. (The player of the fighter, who is oblivious to all of this, is expected to act accordingly.) I've found that doing that cuts out pretty much all of the worst behaviours.