Mortas D. Kettle is a member of the 4th division of The Black Heart Pirates. She is an archaeologist and scientist.
Mortas is a tall and slim woman, with an androgynous appearance that usually makes other people confuse about her gender. She has white skin, short blue hair with pellets all over it that reflect the sunlight, making it shine; and heterochromatic eyes, one being blue and the other white, the later being artificial and emanating radiation due to its composition.
She wears a white, skin-tight garment covering the upper part of her legs, much like shorts, and her torso, except her arms, with an opening in the upper part of the back. It has a collar and a partlet-like design on the front, with a cravat of white silk around the neck and short sleeves of the same material covering part of her upper arm. After losing both her arms, Mortas implanted two dials on her shoulders that allow her to produce and control a special type of alloy composed of Fleurune's clouds and other materials that can change their shape at her will. She wears a pair of white stilettos.