Princess Principal/Recap/S1/E09 Case 20 Ripper Dipper

Quoting from Wikipedia: "The team must keep surveillance on Lord O'Reilly in order to find out the identity of the mysterious person he is meeting in secret. While the other team members keep watch from a hotel room, Ange poses as an artist outside O'Reilly's hotel. While on her post, Ange sees an impoverished girl named Julie who unsuccessfully tries to pickpocket people. Feeling pity for Julie, Ange teaches her how to properly pickpocket. She then tells Julie her past, veiled as a fairy tale. Ten years ago, Ange was not only really named Charlotte, but was the real Princess too. She had quickly gotten bored with her dull and sheltered life, regardless of the comforts of royalty. One day, she discovered a crack in the castle wall where she met Princess, the real Ange, who was a poor pickpocket at the time and looked identical to her. They both quickly became friends. Eventually, Ange grew curious about life outside the castle, and switched places with Princess, and quickly discovered the poor living conditions of the rest of the country. Back in the present, with Julie's help, Ange figures out that O'Reilly's contact is Gazelle. In return, Ange frees Julie from her abusive guardian and helps enroll her and others into an orphanage. Ange finishes her story, where both she and Princess were separated after the Revolution, and how Princess had to live in constant fear of discovery for ten years. Meanwhile, Princess meets O'Reilly and warns him that Gazelle is attempting to trick him defecting to the Commonwealth to trap him, and offers her help instead. Afterwards, Ange admits to Princess that she considers her the true Princess now due to her dream to change Albion for the better. The two then play piano together like they used to do as children."


 * Wham! Episode: For everybody who didn't notice the clues about a relationship between Ange and Charlotte in earlier episodes. "Ripper Dipper" took those clues and removed all the Les Yay, sending the plot in a completely different direction.