Edward Grove
From Tardis Wiki, the free Doctor Who reference
Edward Grove was a sentient Edwardian house, alive only during the moments of the chimes of midnight. It created a two hour time loop and fed on the lives and deaths the servants of the house. At midnight the people came to life again, and the loop started again.
When the Eighth Doctor and Charley Pollard went to the house in "1906", they created a paradox which made the house stronger. When they saved the scullery maid, the paradox and the time loop were broken and Edward Grove was defeated. (AUDIO: The Chimes of Midnight)