Sylvia Slitheen

A member of the Slitheen family posed as Sylvia Dillane, using her skin as a suit. She was killed when a missile hit 10 Downing Street. (TV: World War Three)

Post-mortem
Another group of Slitheen that attempted to drain Earth's sun of its energy in 2008 were motivated in part by the loss of the Passameer-Day Slitheen. (TV: Revenge of the Slitheen)