Nessican

Nessican was a vampire assassin who, with his partner Cain, was sent to Earth by Tannis to kill Valentine and Antenor, Time Lords known as "the Saints" and members of the Fraction. He had escaped from imprisonment in a phantom sun and had no intention of returning, but was poisoned in the London sewers after drinking the blood of the Seventh Doctor who had just eaten garlic. (NOTDWU: Death Comes to Time)