There are not many performers who can steal even an iota of the spotlight away from Beyoncé when she’s locked in. But in Black is King, her new visual album released last week on Disney+, an intriguing figure returns again and again to demand viewers’ attention. He wanders gorgeous African landscapes pensively, eyelids heavy and skin painted so blue as to appear almost translucent; he dances side by side with Beyoncé, hips jerking, tongue flailing outward. That man is Stephen “Papi” Ojo, a self-taught 22-year-old Nigerian-born performer who has quietly played an outsize role in bringing African dance to American stages.