Little Miss Gotham

Sophia Thompson is the daughter of the mayor of Gotham City; a place she dreads and knows will never compare to Metropolis as much as her father tries. As she strives to leave the city with ambitions that go farther than her family's, she's stopped dead in her tracks by the one and only, infamous, and completely insane Joker.
While Harley's stuck in Belle Reve Prison and Joker's out of Arkham, he's in desperate need of a new accomplice and who is better than the daughter of the mayor himself? After psychologically torturing Sophia onto his side, the two of them stir up crime in Gotham that was believed to have calmed down. But the more time they're together, the harder it is to hide Sophia's secret, criminal identity and it's villains against villains in Sophia's new world.
On top of all of that, she just may be falling for the most ruthless, heartless, and emotionless man in the world.