Despite seeming standoff-ish and cold even to the point he appears emotionless, Ayatsuji is a very intelligent man, often choosing not to speak at all though he's always analysing. Despite seeming very quiet and strange, he has a soft spot for certain people and also enjoys teasing others quite a lot. He's blunt and has no problems telling people when he thinks they're being an idiot. He has no memories of the past but has learned his name and that he's a genius.