Plennus

Plennus Donec Tristique Barett is the main character in Plennus' Own Show.

Personality
Plennus is a very childish man who throws temper tantrums when he doesn't get what he wants, these tantrums can vary from a few minutes to sometimes spanning half a episode's runtime. Other than that, he is very happy-go-lucky when he gets what he wants, and won't normally cause tantrums when he doesn't want anything.

Trivia

 * Plennus' full name is an insult if you translate it. Plennus is Latin for childish, and Barett means fraud. However, Barett is also German for "bear strength", and Plennus means multiple things in Latin, but none of these are positive. In addition, "Donec Tristique" means "Dummytennis" in Latin.
 * In season 20, it is revealed that a disease named Plennitis Infanci caused his childlike behavior and size. It normally causes a social disorder named Immature personality disorder, which comes when the disease's victims become 15. Canna does have this too, but she has survived the disorder step, meaning she rarely throws temper tantrum.