Title: Freak of Nature
Pen² (pronounced Pen Pen) is a warm water erect-crested penguin that lives with Misato Katsuragi. He has a rather high degree of intelligence, and lives in his own custom-made refrigerator. In the series Pen² is a key source of comic relief, though his origins are not addressed. In the Manga, he is said to have been adopted by Misato from her former workplace, where he was subject to genetic experiments. Rather than seeing him euthanized, Misato took him in as a pet (or roommate).