Not only does Sui possesses remarkable intelligent, concentration, and an eye for details. In battle, Sui is able to almost instantly analyzing the Festum he faces and comes up with the appropriate respond. On the other hand, when he is set onto any subject, Sui becomes very single-minded and may even forget about his surrounding and the social cues. Around Rina Nishio, the target of his crush, Sui lost some of his confidence, becoming very self-aware and distracted.
