Giant Ogre of the Forbidden Tower Inuyasha : Season 3 Episode 10

Tsubaki is a priestess who was considered to be on par with Kikyo. She was jealous that the Shikon Jewel was not entrusted to her, so she became a dark priestess. Inuyasha and the others defeat Tsubaki's shikigami, but Tsubaki has already broken the forbidden seal and called forth the demon.