Hanyou no Yashahime: Sengoku Otogizoushi - Ni no Shou

Synopsis

Towa uses a limited amount of demonic energy within Tenseiga to destroy the afterlife imps and save Setsuna. This causes Towa to fall unconscious. Toutousai arrives at the scene, reforges the naginata and names the new blade "Yukari no Tachikiri". Setsuna wakes up and uses it to destroy many demons. Toutousai borrows Tenseiga from Sesshoumaru for a three-day mending. Before leaving, Toutousai warns Setsuna not to die again. While Towa manages to restore her powers, Toutousai instructs Setsuna to find a mystical Kyuuyoukon Root from a two-thousand-year-old Magnolia demonic tree Bokusenou to receive a proper fully empowered demonic weapon for Towa to replace a sword hilt.

(Source: Wikipedia)