Mariah Dillard is the cousin of Cornell Stokes and was the councilwoman of Harlem. However, after her criminal ties with her family shattered her political career, she murders Cornell in rage and succeeds him in his criminal empire. She soon became the second biggest crime boss in New York, controlling most of the organized crimes and gangs that the Kingpin doesn't control. She had her own enforcer and consigliere (number one man) in Shades. Just like Kingpin is opposed by Daredevil, Mariah is opposed by Luke Cage, who continually fights to bring Mariah to justice and take down her criminal empire.
Trivia
Mariah Dillard marks the fifth time Alfre Woodard played a character in Marvel Comics production, the first three times were Dondi Reese, the Queen Mother and a Dora Milaje in the animated series The Black Panther, the fourth time was an angry mother in Captain America: Civil War.