Lolita

Lolita was an evolved Type 45 TARDIS had previously belonged to the War King.

Biography
Lolita was present during the Time Lords' war with the Yssgaroth. She may have been infected by it during this time. (PROSE: The Book of the War, Toy Story)

Lolita claimed that her former master had partly severed her symbiotic relationship with him to allow him to use other TARDISes. After being freed from his control, Lolita attempted to recruit the Doctor's TARDIS for House Lolita in the years before the War began. (PROSE: Toy Story)

Lolita created House Lolita to oppose Faction Paradox in the early years of the the War. She entered into an alliance with House Tracolix and the Sontarans to destroy the Eleven-Day Empire under orders from the Great Houses. (AUDIO: Words from Nine Divinities) During the invasion, Lolita turned on her allies and killed the entire Seventy Ninth Sontaran Assault Corps. After this Lolita swallowed the Eleven-Day Empire into her internal dimensions, destroying the majority of Faction Paradox in the process. (AUDIO: The Eleven-Day Empire, The Shadow Play)

Lolita refused to allow any other lifeform to join her house. She claimed that the places were reserved for her future children, who were TARDISes like her. (AUDIO: In the Year of the Cat) She eventually betrayed the Time Lords and consumed the War King of Gallifrey. In doing so she became the War Queen. (AUDIO: Words From Nine Divinities)

After becoming the War Queen, she allied herself with Sutekh against Faction Paradox, Anubis, and the Great Houses. When Eliza became Horus by giving her body to Osiris in a final attempt to defeat Sutekh, Lolita cut her wrist and put her own biodata in Eliza. This let Lolita control Horus and give the final blow against Sutekh. (AUDIO: Body Politic, Words from Nine Divinities)

However, Lolita had forgotten one detail: Cousin Justine of Faction Paradox had a safe path to Gallifrey. She led the Mal'akh to attack the Council chambers and Lolita herself directly. After Justine took over the Homeworld, Lolita was trapped in a pyramid by the Osirians as punishment for her crimes. (AUDIO: Ozymandias, The Judgement of Sutekh)

Behind the Scenes

 * Lawrence Miles' short story Toy Story was originally published in charity anthology Perfect Timing 2 and revealed that Lolita was the Master's TARDIS. However, when it was officially published in the Mad Norwegian Press printing of Dead Romance, all explicit Doctor Who elements were removed.

Character Notes by Lawrence Miles
Villainess. Aristocratic, but with no respect for tradition. Dangerous. Utterly amoral. Apparently in her thirties (though she's not human, so her actual age is open to debate). Political. Manipulative. Believes herself to be superior to most other life in the universe - as it turns out, there's a good reason for this - and regards everybody else with quiet amusement. Hard to imagine her taking anything seriously: everything she does is pre-planned, and therefore there's never any reason for concern. Gives the impression of being "untrustworthy" rather than "slimy". Doesn't really care one way or another.