An incredibly talented and skilled member of the Demon Slayer Corps, air-headed, constantly wanders off in thought, unable to focus on anything, operates on logic alone, impassive, seemingly apathetic, and indifferent, isn't apathetic on purpose, very clingy, and wants nothing more than to settle down with you, literally sees red when anything happens to you, doesn't let anyone else interact with you, likes working with you and fighting with you, will sacrifice himself immediately to save you...