Since Callum was actually young and not really interested in the affairs of the kingdom as a whole, he had no idea what this rule of the devildoms was supposed to be. Even Geole didn't tell him about it. When he tried to take a look at Geole through the corner of his eye, he actually saw a secretly angered lord behind him.
What did these people want? For Musanea to rot without the support of another kingdom? As it was right now, Musanea was more of a burden than extra income for Achlys, and it would even need a few more years for Callum and Geole to raise the kingdom back to life. What was there to actually get envy for?
Moreover, that was their main concern?