Repair droid 7

Repair droid 7 was one of the Clockwork Droids operating on the SS Madame de Pompadour. It was disguised as a female, yet its voice was of a low tone.

History
The Tenth Doctor, Rose Tyler and Mickey Smith witnessed this droid reveal its presence to a young Madame de Pompadour through a time window aboard the ship. The Doctor crossed over to her time period with his companions and hosed it down with a fire extinguisher gun taken from the SS Madame de Pompadour. Knowing that the Clockwork Droids listened to her, the Doctor had Reinette order it to answer all their questions, learning that the droids sought her as the final component to fix their damaged ship. However, repair droid 7 assessed that she was not "compatible" yet. Reinette ordered the droid to leave, and it complied for the time being.

Repair droid 7 later returned with the other droids to capture Reinette when she had recently turned thirty-seven, the same age of their ship. The droids thought this would make her compatible to repair it. However, the Doctor burst through their sealed time window on horseback, rescued Reinette and explained to the droids that they had become purposeless after the link to the SS Madame de Pompadour had been broken, they had no way to return and their mechanical hearts would eventually quit ticking. The Doctor forced the droids to accept that their duty was over and he would not wind them up, either. All of them shut down forever. (TV: The Girl in the Fireplace)

Behind the scenes
Repair droid 7 was listed as "Clockwork Woman" in the Girl in the Fireplace credits.