Mejiro McQueen is one of the many members of the Mejiro Family along with Mejiro Ryan, Mejiro Dober, Mejiro Ramonu, Mejiro Palmer, Mejiro Ardan, and Mejiro Bright.

Born into a family of racing legends, Mejiro McQueen is a long-distance runner who is the envy of her peers. She has class and decorum befitting her prestige, and is determined to take first at the Tenno Sho like many Mejiro racers before her. On her days off, she enjoys having afternoon tea with the many other residents of the Mejiro estate.

She is a petite umamusume with bright lavender hair, she has brown tips on her ears and a teal ribbon on her right one. Her eyes are violet and they have white highlights in the center. She seems to consistently look worried. She wears a fancy racewear consisting mainly of Black, White, and Gold with some cyan details and a cyan ribbon, she has a short skirt, wears blue long socks, and black long boots.

She has many friends, Tokai Teio being her best friend and her rival st the same time, she’s also friends with Gold Ship whom adores annoying McQueen for no reason half the time, her friend Rice Shower, her childhood friend Mejiro Ryan and lastly her roommate Ikuno Dictua..