Minor transgender in "Doctor Who"

[lbh]

Spoiler Warning----------------------In the season finale of DW titled "Hell bent" the Doctor is confronted by a Time lord General (the same one from "The Day of the Doctor" ) he takes his Stazer weapon and threatens him with it. When the General says that it has no stun setting he asks him how many regenrations he's had, when he answers the Doctor shoots him. As he escapes the General regenerates into a young black woman. Not much with the character after that, it happens within the first half hour