K. Lumsy originally worked with King K. Rool but stopped after not wanting to hurt the Family. As a result, K. Rool locked up K. Lumsy on a small island attached to K. Rool's Mobile Island Fortress. Eventually, Donkey Kong arrived and agreed to help set K. Lumsy free and the giant Kremling opens the way to Jungle Japes.
K. Lumsy's role in the game is major since his happy stompings allow access to the other levels. In order to do this, the Kongs must bring K. Lumsy the Boss Keys that K. Rool gave to his strongest henchmen. After giving the Boss Key to K. Lumsy, he will start stomping around which reveals the way to other worlds. After getting the last Boss Key, K. Lumsy is free and helps in beating down K. Rool.
- K. Lumsy is one of few Kremlings in the series to be an ally to Donkey Kong and the rest.
- His name is a pun of "clumsy".
- K. Lumsy is arguably the largest Kremling in the Donkey Kong series.