Penguin-like demons from the Disgaea video game series, and other titles by Nippon Ichi. Prinnies explode on impact when thrown, dood.
Prinnies are the reincarnated souls of humans or other demons who lead a criminal life. It's stated somewhere that you also become a Prinny if you lead a meaningless life.

Prinnies slur the words at the end of their sentences, or in English localizations, say "dood" at the end of sentence, dood.

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