Chishiya is mostly seen sneering even when he is angry unless he becomes emotional or regretful. He is calm, intelligent and highly manipulative which makes him a potential Hearts player. This allows him to triumph in games which require defeating other players. But because he declares himself uninterested in understanding other people's mind, Diamonds remain his preferred genre. Chishiya believes that humans are unconcerned and selfish, but his belief gradually changes after witnessing Arisu and Usagi's selfless acts.