Maybe in the fanfiction, there could be a parallel universe where Kid and Kat have different personalities. They are forced to coop to save both their worlds from destruction. Kat could be more heroic than usual and Kid could be more hesitant, creating an interesting dynamic.
A great plot could be that a strange device has malfunctioned and is causing chaos in their town. Kid and Kat, along with their coop friends, have to figure out how to stop it. Kat uses his agility and Kid uses his wits to come up with a solution.
One plot idea could be that Kid and Fem Kat team up in the coop mode to solve a mystery in their neighborhood. Maybe there are strange disappearances of small objects, and they suspect a new villain in town. Another idea is that they have to compete in a friendly competition within the coop setting but end up learning more about each other's strengths and weaknesses.
One common theme could be friendship. Despite the 'vs' in 'kid vs kat', when the 'coop' and 'female kat' are involved, it might show how they can work together and form friendships.
I'm sorry, I'm not aware of specific 'kid vs kat coop x female kat fanfiction' to recommend. You could try searching on fanfiction websites like FanFiction.net or Archive of Our Own.
One popular character to include could be Coop's sidekick or pet. It could add some comical relief to the story. Another might be a mentor - like figure who gives advice to Kid and Fem Kat during their adventures.
To make your fanfiction stand out, research different writing styles and try to incorporate elements from those that you like. Use vivid descriptions to bring the world of Kid and Kat to life. For instance, when describing a fight scene between them and an enemy, use strong action verbs and detailed imagery. Also, don't be afraid to explore deeper themes like friendship, loyalty, and growing up within the context of the 'kid vs kat coop x kat' universe.
One idea could be that Kid and Kat end up in a strange new world together and have to work together to find their way back home, despite their usual rivalry. They could encounter all sorts of wacky creatures and challenges along the way.
Perhaps the OC is a new kid in town who is initially scared of Kat but then discovers a hidden connection between them. Maybe they both come from the same alien origin, which changes the way they interact and fight.
Well, here's an interesting plot. There's a big storm coming to town. Kid wants to protect the town with his inventions, like building a huge umbrella - like structure. Kat, on the other hand, sees the storm as an opportunity to have some wild adventures. He starts running around, causing more damage. Kid has to stop Kat while also trying to keep the town safe. Also, a plot could be that a famous cat - trainer comes to town and wants to take Kat away. Kid has to prove that he can take better care of Kat and that Kat is better off staying with him. This leads to a series of challenges and competitions between Kid and the cat - trainer.
Once upon a time, the reader was walking in the neighborhood when they stumbled upon Mr Kat. Mr Kat was up to his usual antics, plotting against Kid. The reader, being a kind - hearted soul, decided to intervene. They tried to reason with Mr Kat, explaining that Kid was just a kid having fun. Mr Kat scoffed at first, but as the reader continued to talk, he started to listen. In the end, Mr Kat and the reader formed an unlikely friendship, and Mr Kat decided to give Kid a break.
A possible plot could be that the Reader moves into the neighborhood where Kid and Mr. Kat live. The Reader is intrigued by the strange relationship between the two. One day, Kid accidentally breaks something of Mr. Kat's while trying to show off in front of the Reader. Mr. Kat blames Kid and they start arguing. The Reader steps in and suggests they work together to fix it. As they do, they start to understand each other more and the Reader helps them build a better relationship.