Jenny Flint

Jenny Flint was the wife of the Silurian Madame Vastra. They operated from London in the late 19th century.

Biography
Prior to meeting the Doctor, Jenny had grown accustomed to a life of solitude — she was ostracised by her family due to her "preferences in companionship." By 1888, she was living with Madame Vastra in London. (WC: The Battle of Demon's Run: Two Days Later)

Among the many allies the Eleventh Doctor had recruited for the Battle of Demons Run, she along with her lover were among the few to survive the attack of the Headless Monks. She comforted Amy Pond afterwards. (TV: A Good Man Goes to War)

Two days after the battle at Demons Run, Jenny and Vastra waited for the Sontaran Commander Strax to fully recover from the wound he'd suffered. When Strax awoke, he initially believed himself to be dead and was resistant to believe that he hadn't died honorably in battle. Jenny accused him of merely fainting. Jenny and Vastra asked him if he'd like to return to Victorian London with them. At first he refused, but accepted their offer at the last minute and left with them as Demons Run was being evacuated. (WC: The Battle of Demon's Run: Two Days Later)

Jenny and Vastra, alongside the Sontaran Strax, summoned the Doctor to the London of their time, asking for his assistance. The Doctor refused, claiming he had "retired." (TV: The Great Detective)

By Christmas 1892, Jenny and Vastra were married. Jenny was involved in the defeat of Walter Simeon and the Great Intelligence. She and Vastra confronted Simeon. She later found Clara Oswald looking for the Doctor and took her to see Vastra. Clara explained the situation with one word for each question Vastra asked due to the fact that Vastra and Jenny had made her do the "One Word Test." Jenny later trapped the Ice Governess behind a force field and stayed with Vastra and Strax to guard the Latimer family, while the Doctor and Clara led the Ice Governess up to the Doctor's TARDIS. Jenny was also present for Clara's funeral after the Ice Governess killed her by pulling her off a cloud. (TV: The Snowmen)

In 1893, Jenny went undercover to Sweetville, Yorkshire to investigate a phenomena called the Crimson horror. After breaking away from the new arrivals to investigate the facility, she discovered the Doctor chained up in a cell, his skin bright red and body so stiff that his mouth was frozen open. She rescued him, gave him his clothing back, and together they began to search Sweetville for Clara Oswald. Jenny was shocked to find that Clara was alive and repeatedly tried to get the Doctor to explain how, but all he would tell her was "it's complicated." (TV: The Crimson Horror)

Later, when Vastra invited Strax, River Song, and Clara Oswald to a psychically-linked dream "conference call," Jenny also participated. During this time, the Whisper Men broke into Vastra's house. As the conference progressed, Jenny became increasingly nervous, as sensations caused by the movement of the Whisper Men in the real world leaked through into the dream state. Finally, Jenny interrupted the meeting, revealing that she had been murdered in the real world, thereupon fading out of the meeting. Eventually, after Vastra woke Strax and herself, the Whisper Men transported the three to Trenzalore, where Strax revived Jenny.

As the Great Intelligence, still in the form of Walter Simeon, entered into the Doctor's time stream, Jenny disappeared, being erased from the universe by the Intelligence's actions. However, once Clara sacrificed herself into the Doctor's time stream and effectively undid the Intelligence's deeds, Jenny reappeared along with everything else that had been erased from existence.

Personality
Jenny had a romantic relationship with Vastra, despite the fact that she was a different species and a woman. (WC: Vastra Investigates, TV: The Snowmen) She seemed proud to be married to the Silurian, noting that Dr Simeon had never been married. This commitment to her marriage is further shown when the Doctor kissed her after she rescued him from Ada Gillyflower's cell, although he had no intentions other than to show his gleeful gratitude, Jenny promptly slapped him while clearly looking uncomfortable at the gesture. (TV: The Crimson Horror) Jenny showed jealousy when Vastra showed interest in others. Jenny was also quite sarcastic at times. For example, she replied, "Thank you," to Vastra's comment that mammals all looked alike. Her sarcastic nature was also shown when she said, "At your service," to Simeon. (TV: A Good Man Goes to War, The Snowmen)

Despite being a feisty and fierce warrior, Jenny was also compassionate and comforted Amy about the loss of her child. She also told Amy that it wasn't the Doctor's fault that Melody Pond had been kidnapped. (TV: A Good Man Goes to War)

Abilities
Jenny was quite capable in combat — she survived the Battle of Demon's Run without any injury. She displayed excellent skills with a sword during the battle. (TV: A Good Man Goes to War) She also fought off attackers when confronted in Sweetville, until The Doctor forced her to flee. (TV: The Crimson Horror)

Spin-off?
Since their first appearance, Vastra and Jenny became popular characters in fandom, with fans wishing for a spin-off series to be made based on their adventures. Steven Moffat addressed this, saying that he considered making a spin-off when he created the two characters, but wouldn't have the time, though he said he would like to revisit them.

The Brilliant Book 2012
According to The Brilliant Book 2012, a book that contains non-narrative based information:
 * Jenny was a match girl when she first encountered Madame Vastra. She was being molested by a Chinese gang called the Tongs, from whom Vastra saved her.
 * On one occasion, Jenny helped the Doctor defeat a Kraal plot to replace Prince Bertie with an android duplicate while Vastra was in Egypt.
 * At one point, she and Vastra battled a pair of CyberNeomorphs in feudal Japan.
 * Following their return to their own time, Vastra and Jenny were added to the Papal Mainframe "most wanted" list.