Popo

Popo, formerly known as Lolo, is a gorilla.

History
After Bart helped Lisa free Shame-u from Aquatraz Water Park, he got addicted to altruism. Bart started to look for more animals to save, finding a video of Lolo. Lolo could use sign language to sign five words; "friend", "enemy", "kill", "vodka" and "Seinfeld". Bart then decided to free Lolo from the Springfield Zoo, with the help of Milhouse. After they showed Lolo how to get out of her enclosure, Lolo escaped into the city, causing destruction along the way. Bart then went to Lisa to get her help.

Bart and Lisa then went to Springfield Elementary School where Lolo was attacking Principal Skinner and Superintendent Chalmers. She then put on an episode of Seinfeld to calm down Lolo and gain her trust. The Simpsons then took Lolo to Pennsylvania Ape Reserve where Dr. changed her name to Popo and let her live free in the reserve.