Firese was a small avian demon, he had a small triangular body with bones visible under the skin. Sprouting off the body was a long thin tail and large bat like wings. A large cluster of horns sprout on the top of his head. He had a wicked face with pupiless eyes.
Firese is only shown to be capable of flight during his brief appearance in the story.
After Zennon had announced the forthcoming demon invasion across the world, it took only five minuets for a swarm of devils to begin descending down upon the cities of the world, killing and destroying all they could.
Firese is amongst the swarm of devils that attacked Japan after Zennon's speech. He could be seen in the skyline alongside Millage, Yuniotti, Tellestlle, the Unnamed Fuzzface Demon, the Unnamed Leg-Winged Demon and the Unnamed Hammerhead Demon.