Yellmo is an Elmo-esque creature, just like his cousin, Wabemo. He is known for yelling, and his reign of terror in Peskite. He now dissapeared from Venture, and is rumored to be sailing the seas of time. However, he was later found dead with a knife lodged in his chest. Yellmo was murdered in cold-blood by none other than his cousin- ELMO himself.
Yellmo hates Wabemo, just like all of his family. He even even shoved him into the sea because Wabemo was being a 'dick'.