Hmm... I don't... think so? I don't think she fits into one of the -dere character types, since she's extremely devoted to LORD-SAMA, but it's everyone else who gets ultra-seriousness or disapproval. Well, at least if they act in ways she does not approve of, otherwise it's just ultra-seriousness, eh-heh.

... Or Akako becoming a quivering mess of embarrassment if perversity is directed at her but yeah.