Sky Silvestry
Sky Silvestry was a businesswoman and apassenger aboard a tourist craft on the planet Midnight.
Biography
She was visiting Midnight after the end of her relationship with her female partner. When an unknown force began banging on the side of the vessel, Sky panicked, imagining her former lover had returned to get revenge. The force, apparently feeding on her fear, possessed her.
It is not known whether Sky Silvestry's consciousness remained afterward.
When first possessed, Sky repeated everything that everybody said,. Then she said the same thing at exactly the same time. The other passengers were terrified by this and decided they wanted Sky thrown off the bus to her death, which the Tenth Doctor objected to. Skybegan to speak only in the Doctor's voice and then speak before him. The other passengers believed the lifeform had left Sky and had now possessed the Doctor, but in reality.
Sky convinced the others to chuck the Doctor off the bus. The Hostess realised Sky was still possessed due to her use of the phrases "Allons-y!" and "Molto bene". These were phrases the Doctor had used earlier in speaking to her. The Hostess grabbed Sky and pulled her out the door, sacrificing herself and Sky to save the Doctor. (DW: Midnight)