Pen Pen

No living penguin matches Pen Pen exactly; among real species, the erect-crested penguin comes nearest. He departs from actual birds in visible ways, most obviously the three retractable claws on each hand, equipment nothing in nature carries. His nameplate bears the serial number BX 293A.

Pen Pen behaves less like a pet than a small housemate. He watches television, pages through newspapers, soaks in hot springs, eats what the humans eat, and drinks beer, and the series quietly implies he tracks the events around him with near-human comprehension.

His presence fuels recurring comedy, most memorably in the early days of Shinji and later Asuka at the apartment, each of whom is startled to discover him already occupying the bath they were about to use.

Misato apparently brought Pen Pen along when she left her previous posting, houses him in a second freezer in her apartment, and insists he counts as family rather than a pet. He stays part of the household until Zeruel's devastating strike on Tokyo-3, after which a saddened Misato sends him to live with Hikari Horaki's family so he will be safe.

Yoshiyuki Sadamoto's manga gives him a fuller backstory. There he is a Fiordland penguin whose intelligence came from a genetic experiment; once the testing ended he was to be killed, but Misato took pity on him and made him her pet, setting up a small refrigerated room to approximate his natural climate.

On the production side, the name simply repeats the pen of penguin, officially rendered as Pen squared. The staff wanted an animal mascot, and since Tokyo-3 sits on Hakone, hot-spring country associated with monkeys, they went the opposite way and picked the animal least suited to a hot spring, an idea credited to Sadamoto. Early design documents state the genetic-manipulation origin outright and give his age as two, and some speculate the 1986 anime special Mr Pen Pen also fed into the character. Megumi Hayashibara voices him in Japanese.