In the campaign that Order of the Stick is set in, Belkar's player is a problem player, and the DM is trying to teach him to cooperate with the group more and be less disruptive.

Evidence:

1. The vision Belkar had from Lord Shojo telling him to be more of a team player. It was established in one strip (IIRC) that Shojo was an author avatar for the DM.

2. The oracle predicting Belkar's death. Might be because the other players felt that they couldn't continue on with Belkar disrupting everything and wanted Belkar's player to roll a new, less disruptive character.

3. The fact that he's chaotic evil, while the party leader is lawful good.

4. Killing that random gnome who wasn't an opponent, and having Hayley tell him in character that the gnome was just there for "flavor."