She is a former member of Shuro's group and currently a part of Laios' group.
Izutsumi first appears wearing a black outfit with a veil that covered all of her face except her eyes. She later loses the veil, and is seen wearing a ninja-like outfit with a covering for her hair and ears.
She is later revealed to have black cat-like ears on the top of her head, with a white tip on her right ear, and a white-tipped tail. She is in fact is covered with fur all over her body, mostly black with patches of white covering her front, right hand, left arm from hand to upper arm and right leg from foot up to mid-thigh. Her nails are closer to claws, having pointed tips, and she has fangs in her mouth.
Izutsumi is not actively aggressive towards those around her but she is prone to becoming annoyed and hostile, especially when showered with physical affection (e.g. head pats). She is rather stand-offish but is not a distant person. She tends to be fairly self-centered, but is in the process of learning the value of working with others. She is capable of finding rapport with others and is even able to find her place among her peers. Izutsumi is primarily fueled by a determination to find someone to lift her curse. She can be impatient to achieve this goal, which manifests in frustration due to what she perceives to be the slow progress of Laios' group through the dungeon. She has terrible table manners and is a picky eater. She has a tendency to offload unwanted duties onto others.
Izutsumi was born to humans, but the nature of her first curse, the curse placed over her which fused her body with that of an animal's is unknown. In her youth, Izutsumi was paraded as a circus freak. Eventually, Izutsumi was bought by Shuro's father to be raised as a retainer. After being bought, a second curse was placed over Izutsumi by one of the other retainers, which involved a knife-wielding spirit attacking Izutsumi unless the brand of the curse was regularly touched by the person who set the curse on the victim.
(Source: Dungeon Meshi Wiki)