Tsukiyomi

was a human priestess who once hunted demons. At her side was a demon, her love, who changed his name to Hoshiyomi because of her and the love he bore for her.

Together the two fought a variety of monstrous beasts and in the course of these battles the priestess Tsukiyomi was forced to use immense amounts of her spiritual powers to defeat them. This use of her power slowly drained Tsukiyomi's very own life force weakening her greatly bringing her closer to death each time. Hoshiyomi, in an effort to protect Tsukiyomi from draining herself by using her powers too often, had a demonic weapon created, the Naginata of Kenkon. A weapon forged using the essence of a great number of demons. But the Naginata of Kenkon is too strong, and begins to possess Hoshiyomi. In an effort to save him, Tsukiyomi attempted to seal Hoshiyomi away until she could purify the evil weapon. Tsukiyomi successfully separated the Naginata into two swords, the Ken blade and the Kon blade, and the blades far away from one another, but at the cost of a tremendous amount of her spiritual powers and ultimately her life before she could free Hoshiyomi.

Hoshiyomi is released when a sacred barrier around Mount Hakurei is dispersed, allowing him to find the Kon blade. He seeks the Ken blade, which was held by the Hōjō family. Akitoki Hōjō bears the Ken blade to the Furai Shrine at Shoun Falls where the blade can be purified.

After recombining the two blades back into the Naginata of Kenkon, Hoshiyomi is confronted by the spirit of Tsukiyomi whom he blames for betraying him. She tries to explain what had happened, but Hoshiyomi is too consumed with rage. In the end, Tsukiyomi replenishes Kagome's spiritual power so that she and Inuyasha are able to overcome Hoshiyomi and the Naginata of Kenkon.

Abilities
Dispatching Demons: Tsukiyomi was able to dispatch demons with a wide range within her spiritual power, which usually drains a majority of her energy.

Sealing Demons, etc.: Tsukiyomi was able to seal demons and evil with her spiritual immense powers along with star-shaped object. Before the sealing, a slogan "臨兵闘者皆陣列在前, Rinpyōtōjakaijinretsuzaizen" speaks out, but was not able to seal demons and other malicious objects numerous times for the reason that it takes about 75% of her spiritual strength. Thus, Tsukiyomi disintegrates into ashes once she seals the Naginata of Kenkon.

Undoing Spiritual Rituals: Tsukiyomi, as demonstrated by Kagome, was also able to undo spiritual rituals preformed by Hoshiyomi at the shrine. Thus, Hoshiyomi hints that Kagome's spiritual power was able to interface with those of Tsukiyomi.

Separating the Naginata of Kenkon: Although she was unable to purify the weapon she was able to successfully separate the Naginata of Kenkon in Mount Hakurei and Mount Fuji where the Hōjō family found and treasured it generation by generation.

Purification: Little is known of her purification skills, but it hinted that she had immense spiritual power to purify demons like the ones she fought day by day. It is suggested that Tsukiyomi at one time indeed would have had the power to purify the naginata but that her years of extensive demon fighting had weakened her so much so that she unable to destroy the blade's evil power.