Mutoid Assassin

Ok, this is a slight re-design on the Mutoids from Blake's 7.

Mutoids were modified humans (usually female) that were bred to serve the Terran Federation. Presumably Mutoid is short for Mutant Android, but I don't recall that ever being mentioned in the show. They exist only to serve.

Anyway, Mutoids required no sleep and gained nourishment through tubes of "blood serum" that were plugged into their chest. Opponents of Mutoid modification called them vampires. In an emergency, if blood serum was not available, all Mutoids were equipped with a retractable hypodermic syringe attachment with which they could extract blood from living creatures.

Edit: All characters from Blake's 7 belong to Terry Nation