Lotney "Sloth" Fratelli is a large and deformed Fratelli brother of immense strength from the 1985 movie, The Goonies. He was held prisoner in a room by his mother and often teased and tormented by his siblings. His deformity is the result of being dropped by his mother several times when he was a baby.
While working at Superstore USA in "Hell Comes to Quahog", one of Meg Griffin’s duties is to give him a Baby Ruth candy bar. He then states that he is “already in a committed relationship”, presumably with Chunk.
After Stewie shave his head and Lois convinces him he looks like a celebrity in "Chap Stewie", Peter signs an autograph for a fan whom he thinks believes him to be Bruce Willis, but who actually thinks he is Sloth.