Nanaya is an alternate personality of Shiki due to the blood he inherited from his real family. The Nanaya clan was a family focused on destroying demons. This heritage manifests as an alternate personality known as Shiki Nanaya. The Nanaya side of Shiki is a highly trained killer. Smooth, confident, and highly dismissive of life, Nanaya is a very large contrast with how Shiki usually behaves. This personality awakens when Shiki is confronted with a situation that matches the demon-slaying need, usually when Shiki is in mortal danger, or when he spots something inhuman. When the Nanaya blood awakens, Shiki drops into the fugue state of his anemia attacks; he blacks out and has no memory of what he has done during the time Nanaya was in control. As befitting an elite demon-slaying assassin, Nanaya has highly enhanced strength, speed, reflexes and has all the skills of a highly trained killer. His greatest attribute is speed, as he is capable of running up walls and along ceilings, and moving faster than normal human sight for a fast kill.
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