Like the rest of her family, Nichika had large eyes with pale skin. She wore her short, white hair in a blunt bob with a fringe.
Nichika wore a dark blue kimono with purple flowers and a maroon obi. On the left side of her hair, she donned a yellow ribbon.
Not much was known about her personality, but she does show a sense of loyalty for dying along with her twin sister when their father sacrificed himself to defeat Muzan.
As an ordinary human, she doesn't possess any additional powers or abilities.