Mr. Chunks

Mr. Chunks is a two-headed alien goat. One head constantly pukes and the other constantly pukes diarrhea. Fry and Bender used it to fill up a pool with their barfs and diarrea, so who wins the most Twitcher followers had to jump in it. There was a tie but, even so, Fry jumped in, recorded the video and upload it to Twitcher to stop people from laughing at Leela. The goat later died.

Trivia

 * Polycephaly is an actual condition on humans, but it's more commonly noted on other animals. Multi-headed animals are often depicted in mythology as supernatural and mystical. This is possibly why most people don't believe in their existence.
 * Fry refers to Mr. Chunks as a puke-me-poop-you, possibly its species name, but in any event, a play on the two-headed creature, the pushmi-pullyu, from the classic children’s series Dr. Dolittle.