Kristoff is a stiff man. In his book fun means riding a sled, cutting ice, selling ice, or anything with ice. He usually spends his winters working, and rolling his eyes at the little kids playing with snowballs, building snowmen or making snow angels.
But after meeting Anna, every winter they go outside and play with snowballs, build snowmen, and make snow angels.
He still thinks that it’s childish.
But doing all of it with Anna, he doesn’t really care.