Elektra
From Tardis Wiki, the free Doctor Who reference
Elektra was an Eternal who broke an ancient rule of the Ancient Covenant by mating with a Chronovore, Prometheus, in order to produce the chronovore/eternal hybrid known as Kronos. It was believed that she produced the child in order to lead the chronovores against the great old one, Nyarlathotep, who she feared.
When this was discovered, the Guardians of Time punished her and Promethius by erasing them from all existence. The child she had produced, however, was spared. (PDA: The Quantum Archangel)