9) Buster Baxter (Arthur)
We have our reasons for going after Buster Baxter (geez, what do you take us for? Monsters?), and it's only a matter of time before Arthur and his pals see how much happier they'd be without him. First, the guy's an unapologetic slob, eating out of trash cans and going days without bathing. Second, Buster has absolutely no concept of responsibility—which usually ends with someone else cleaning up his mess under the pretense it's a lesson in teamwork. And lastly, more often than not, arguments between him and Arthur break out over the aforementioned.