Kuro is generally much calmer and more nonchalant than Illya. She is devious and manipulative, picking up on subtleties about people and using them to her advantage, and she can be very brazen and unrestrained in her actions. She has experienced all of the same events as Illya, allowing her to recall events before she manifested. Kuro is deeply bitter as a result of having been sealed, both towards her parents for sealing her, and toward Illya for wishing to be 'normal'. She believes Illya is indirectly wishing for her, the manifestation of her past as part of a Magus clan, to not exist. She places pride in the reason she was born, and wishes to follow it if she can. The idea of being called a second hand clone infuriates her, for the name 'Illya' originally belongs to her.