Hitotoki

""Hinan sa reta"" is a curses demonic sword that layed hidden from mankind til Kyoukou Uzumaki found the blade by sheer "luck" after fighting the three tailed jinchuriki Yagura Karatachi.

The aspects of this blade is still unknown but what is known that kyoukou often hears voices from the sword but only took it as lack of sleep but was fully confronted by the said spirit residing within the blade announcing itself as "Kōka the demon spirit"