Izuna

A small fox/ferret-like spirit send by the Osa of Tono to assist Ushio in his effort to purge the demons possessing Moritsuna. He becomes a good friend and loyal ally.

Personality
Izuna is a clever little yokai, and sometimes his mouth gets him in trouble with Tora whom he sometimes teases with smart remarks, often getting burnt to a crisp in retaliation, and even almost eaten by Tora. Still, Izuna is very smart, helpful, and loyal, helping his allies to the best of his abilities, and he even once took a blow for Ushio to protect the boy.

Still, Izuna can be quite cynical towards humans, as he is very proud to be a yokai. Even so, he genuinely cares for his friends and Ushio, and isn't ashamed to show it, unlike Tora.

Powers and abilites
Though he is small, Izuna is capable of fighting any but the most powerful opponents. He can fly, he has the ability to possesss both humans and yokai, he can travel through mirrors and other reflective surfaces, he's strong enough to barely lift Ushio by his shirt, and even use his flame-like tail as a blade.

Bakegyamon
Izuna is one of the few characters that makes another appearance in Mitsuhisa Tamura's second manga, Bakegyamon. He remains the same however, but does not fight or have a grudge with other yokai, and helps Sanshiro similar to how he helped Ushio.