Pen Pen is a warm-water penguin from the iconic anime series 'Neon Genesis Evangelion'. Unlike any regular penguin, Pen Pen is highly intelligent and possesses a unique personality, often displaying human-like characteristics. He resides in a special refrigerated area in Misato Katsuragi's apartment, adding a light-hearted touch to the otherwise intense and dramatic series. Although Pen Pen does not engage in the battles against the Angels, his presence provides comic relief and a sense of normalcy for the main characters, serving as a beloved pet and companion.