Flemmingrad

Flemmingrad is a troll who is remembered every December by his kind, as per tradition. Kristoff showed the tradition to Elsa and Anna in an attempt to cheer them up after the Citizens of Arendelle went home to celebrate their own traditions.

Part of the tradition consists of a gathering song, building an effigy of the troll and licking his forehead while also making a wish. Parts of the effigy are then used to make "Flemmy" stew.

Personality
Flemmingrad is described by Kristoff as being a "jolly old soul", and was regarded with high esteem by his kind. Young trolls would bring him various types of food, which he happily would eat with great zeal; he was glad at always being full. This led to him being a very large troll, but the children would still take delight in watching him roll.

Trivia

 * In the traditional version of the song, it is implied that Flemmingrad died while trying to escape from humans.