Coco was hired by George Costanza simply because her name was Coco, which was previously a nickname given to George, due to him waving his arms in the air during an argument with T-Bone.
Mr. Kruger realizes that her name is Coco. As such, he lets George go back to his normal name.
After being asked how to get a stain off a building, Coco begins telling everyone about her 'Gammy'. Before being able to finish the story, George interrupts her and says, "No one wants to know about your Gammy." Coco comes back, "What did you say about my Gammy?"
Mr. Kruger then says to George, "Maybe there should be a Gammy." As he says it, he points at George on 'Gammy'.
All the Kruger staff, including Coco, bang their hands on the table and chant “GAMMY! GAMMY! GAMMY!” before George stands up and shouts, "GAMMY’S GETTING UPSET!"