Well, I sorta expected him to be a badass in close combat but holy shit was he brutal. I'm guessing the reason he was so irritated, but it might be because he technically has no parents, but he sees the Duke's family as his surrogate family.
honestly, his reaction to this whole thing pissed me off so much at the time that I dropped the novel for awhile.
He thinks that he lost his self control and needs to distance himself from the duke's family so he can become more disciplined, thinking he's become spoiled. Emotions are a kind of sense too. Being angry in this situation just means you have proper awareness of the context your in.