Kagero Hunter - Akago

Appearance can be deceiving, as anyone who ever came across the child-like hunter of the Kagero sorcerer clan have learned. The man who goes by the codename Akago, resembles a child, physically, and usually acts like one too, however, everyone familiar with him knows he's much older than one would assume. All that is known about him is that he's some sort of fire spirit, with incredible power, and has some sort of ties with the mysterious person who originally founded the Kagero school of magic. His true nature is classified information even among the Shadow Hunters, known only by the Kagetama himself, outside the clan.

Akago resembles a five year old boy with red hair, dressed in flame colored, fire-proof clothes. While most of the people he's familiar with, know he's really an adult (and probably the oldest of the hunters), many people who don't know him, mistake him for an actual child. He's not ashamed to take advantage of the situations as he manages to get away with things normal men of his age would get slapped or megaton-punched for.

He is the only hunter who doesn't carry a clan-specific weapon (besides the Honoga hunter, but their clan specializes in unarmed combat). for combat, he relies solely on his fire based powers, creating projectiles, walls or even entire torrents of hot plasma, to devastating effect. In his spirit state, he can assume the forms of various creatures of pure fire (such as a phoenix).

Akago's name refers to both his appearance, and the creature Toriyama Sekien refers to as Abura-akago, a spirit shaped like a fireball that sneaks into houses transformed into a human child and licks the oil out of the lamps. This description inspired his attire, his powers as well as the fact that he feeds almost exclusively on oil. Early designs featured him wearing shirts with various oil-ads on them but I eventually abandoned the idea because I'm not too fond of product placement, and using brand X in this case kills the joke.
And before you ask, yes, he and the fire spirit from the Council of Ancients are one and the same character. But I'm not linking to that picture because it is old and looks horrible.