One possible title could be 'The Adventures of Harley Quinn and Her Fem OC Ally'.
The Fem OC could be a reformed hero who is trying to stop Harley Quinn from her villainous ways. But as they interact more, they start to understand each other's perspectives and end up teaming up against a bigger threat in Gotham. This would involve a lot of character development for both of them as they learn from each other.
One plot idea could be that the OC is a new villain in Gotham. Harley Quinn becomes yandere for the OC because of their unique style of chaos. She starts to stalk the OC, leaving little gifts that are both disturbing and endearing, like a dead bird with a love note.
One idea could be that the OC is a new villain in Gotham and Harley Quinn takes an immediate liking to their chaotic style. They team up to pull off a heist on one of Gotham's richest, with Harley's unpredictable nature and the OC's unique skills making for an exciting adventure.
One great 'oc x Harley Quinn fanfiction' is 'Harley's New Ally'. In this story, the original character (oc) is a vigilante who crosses paths with Harley Quinn. They start off as enemies but gradually develop an understanding. The author does a great job of capturing Harley's complex personality and how the oc challenges her views. It has some really interesting action scenes and character interactions that make it a fun read.
A popular one is 'Harley Quinn and the Reader: A Gotham Adventure'. This fanfic is exciting as it takes the reader on a journey through Gotham's underbelly with Harley. The author's description of the city and the interaction between Harley and the fem reader makes it a must - read. There are some really intense action scenes and some heart - warming moments too.
A simple title could be 'Emma Frost and Her Fem OC: An Unlikely Bond'.
A good 'oc x Harley Quinn fanfiction' often has unique plot twists. Maybe the oc has a secret that changes Harley's perception of them completely. Or perhaps Harley has a goal that the oc initially opposes but later comes to support. The story should also have good writing in terms of grammar and style. If the writing is sloppy, it can be really hard to get into the story. And the fanfiction should explore the themes that are relevant to Harley Quinn's character, like freedom, madness, and the search for identity, through the relationship with the oc.
One idea could be that Batgirl and Harley Quinn are forced to team up to take down a new supervillain in Gotham. They start off as reluctant allies but gradually come to respect each other's skills. For example, Batgirl is impressed by Harley's acrobatic skills and Harley is in awe of Batgirl's detective work.
Perhaps the fanfiction could revolve around a love triangle. The reader is caught between Harley Quinn and another well - known Gotham character, like the Joker. This would create a lot of tension and drama as the reader has to decide between Harley's wild charm and the allure of the other character. It would also test Harley's possessiveness and loyalty.
A third option could be a fanfiction set in an alternate Gotham where Harley Quinn has turned over a new leaf. The reader is a civilian who meets Harley at a local coffee shop. Harley is trying to blend in and start a normal life. The reader is initially hesitant but soon realizes that Harley is more than her past actions. They begin a relationship that is filled with challenges as they face the judgment of Gotham's citizens.