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And here's a little bonus for the demon kingdom, as well as some story context.
Rulf is a commander in the Demon army, and he controls most of the SPED/cripple kids (Georgina betrayed him to go be a princess). Rulf hates serving under Max and very obviously wants to take over for himself.
At one point in the story the new kid is separated from his friends and cornered by Black Knight Rosalind, Jester Neil and Dark Mage Mineral in North Park elementary. However, this is when Rulf reveals his true intentions and traps the four of them inside the school so that he'll be able to find the book for himself without them being able to interfere.
This leads to the new kid forming a temporary alliance with Rosalind, Neil and Mineral who become party members until you fight through the school defeating the different cripple kids and minibosses until you find Rulf and kick the shit out of him as well. After this the new kid and his unlikely teammates go their separate ways, but it builds up some positive respect between them so they are more likely to team up with the new kid later when Blenny betrays Max.