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.
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.
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.
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.
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.
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.
Once upon a time, the Reader found themselves in the middle of the chaos between Kid and Mr. Kat. Kid was always up to his mischievous antics, much to Mr. Kat's annoyance. The Reader decided to try and mediate. They talked to Kid, explaining that Mr. Kat was just trying to keep things in order. Kid was hesitant at first but then started to listen. Mr. Kat, seeing the Reader's efforts, was also more open to Kid's youthful energy. In the end, they all found a way to coexist more peacefully.
In a world where Kid and Kat co - exist, Kid noticed that Kat had been acting strangely lately. Kat seemed to be spending a lot of time in the old abandoned house on the edge of town. Kid, being the curious boy he is, decided to investigate. He snuck into the house one day only to find that Kat was building a giant cat - like contraption. Kid realized that Kat planned to use this to take over the town's supply of tuna. So, Kid quickly ran back home and started to build his own device to counter Kat's plan. After days of hard work, Kid was ready. He confronted Kat just as Kat was about to launch his contraption. A battle ensued, with Kid using his smarts and Kat using his feline agility.
In this 'kid vs kat flu the coop fanfiction story', it could start with Kat showing some strange symptoms that the Kid suspects might be flu. So, the Kid decides to take matters into his own hands. He first tries to isolate Kat from the coop. But Kat being Kat, doesn't like this idea and tries to break free. This leads to a series of comical chases around the coop as the Kid tries to keep Kat away from the other animals. Eventually, the Kid discovers a natural remedy that cures Kat and saves the coop from the flu.