Stahl’s “angry” (not “smirking”, but that one’s rare too) portrait is probably seen only twice in the entire game: the end of Chapter 10, and Endgame. If you use him and think it’s familiar somehow, it’s the same eyes used for his critical hits and skill activation. For all of his awkwardly sweet and mild chew-toy status in supports, he is a devoted knight of Ylisse and a damn serious one when it comes down to it. He and Sully were personally taught by Frederick, the super butler-knight whose mere recruit training is supposedly something out of Hell’s workout videos. Even when he’s placed as the median of all Shepherds, he’s willing to push himself to his limits when required. His appetite’s likely justified when he needs all those carbs and protein. Also, you don’t fuck with the guy who will shout “I love this part!” as he charges and slashes a brigand to pieces.
To end this on a somewhat derailed note, I find characters bearing a demeanor different from what one’s used to, but reasonably within character, very aesthetically pleasant. Stahl here is no exception, good heavens he’s handsome.