Gasoline.

This story isn't not your ordinary fanfic, this is about two criminals battling it out for Gotham city, when they finally meet each other and they "tempt fate" if you will. This is based after the film suicide squad and Harley has left the joker.

The story will mainly be in 1st person from Talia's point of view. Taliah is from Gotham born and raised, her "criminal" name is "Empusa" which means demon. She is the demon of Gotham city but so is someone else? The joker..

This is based one:
Mental disorders
trauma
Matureish