Goose God is a muscular anthropomorphic goose who happens to be a god, seemingly of Greek or Roman origin based on his outfit. He could draw inspiration from Zeus, specifically him appearing as a goose, or a swan.
During The Gods Must Be Goosey, he is lonely and wants a queen to rule the heavens with, so he falls in love with Muriel, making her numerous visits and offerings of gifts, such as an endless field of flowers. Courage attempts to thwart him, despite Eustace paying much more attention to his truck than the situation going on around him. After Muriel kindly spurns his advances, saying that she is happily married, he refuses to take her kind "no" for an answer and decides to take her instead. As he begins to ascend with her into the heavens, Courage attempts for the last time to get Eustace to help. Accidentally knocking him out while working on the truck, Courage presses the truck's horn, which sounds pleasant to the Goose God. He falls in love with the truck, and takes it with him to his home in the clouds.
He is later seen again during the family's holiday in Norway in The Ride of the Valkyries. The Valkyries, who continuously sing as they talk, sing about how they have lost their sister, and need to find her before the next days' battle. The Goose God is seen sleeping on a cloud with the truck, and complains that he and "Truckie" are trying to sleep.
The Goose God was a lonely Goose who wanted a queen to rule the heavens by his side. He was very persistent and charming. He is now happy with Eustace's truck, or "Truckie" as he calls it.