Sarah J. Maas said this quote
“ He felt as if there were something missing inside him that didn't fit in with their merriment, with their willing ignorance of the world outside the castle. It went beyond his title. He had enjoyed their company early in his adolescence, but it had become apparent that he'd always be a step away. The worst of it was that they didn't seem to notice he was different- or that he felt different. Were it not for Chaol, he would have felt immensely lonely. ”