Mirror demon

The Mirror demon was a living incarnation of Kanna's mirror. In unleashing it, Kanna revealed how truly powerful she could be. It was used as a last-ditch attempt by Naraku to defeat Inuyasha. The demon stole/copied the techniques used by the Tessaiga and redirected them against Inuyasha. When struck by a strong physical attack, the mirror demon would automatically repair itself, and the damage would be transferred to Kanna instead. Inuyasha realized that Kanna and her mirror were linked, and reluctantly continued to bash the demon until Kanna was unable to suffer anymore damage. Byakuya, who had accomanied Kanna, noted that the more direct, efficient way for Inuyasha to fight the mirror demon would have been to strike at Kanna herself, and destroy the demon immediately. However, Inuyasha insisted on persuading Kanna to stop fighting, feeling pitying her since he knew that Naraku was prepared to use her as a sacrifice to take out his enemies.