I mean truly, Pugman made a better pitch for joining Desir's party than anything Desir could have told her. I mean, she wants to get stronger, and that can be done as well from the position of a rival than a comrade. so long as you knew her motivations, it wouldn't have been all that hard to keep her cooperation, which would be invaluable, if you considered that she's a godsdamned Magic Swordsman who can actually manage a Magic Sword in Year FUCKING ONE, not to mention, y'know, a princess. If you've got a chain, you don't tug it to see how much it can take before it gives, you check to make sure it's securely fastened to whatever you're trying to keep from getting away... or keeping at bay. I mean, the Nipheleka family and Roguepalace apparently have a good relationship, it'd be a shame if something happened to change that.
For a moment, I thought his seeming idiocy was playing the political game (and thus evil, but not evil and stupid), but sadly no; this asshole obviously believes in whatever bullshit he's selling and couldn't hatch a plot to save his life.