A more complex plot might be that Naruto's immortality has some unforeseen consequences in Kim Possible's world. It starts to disrupt the balance of magic or technology there. Kim and Naruto must then figure out how to reverse or control these effects while also dealing with villains who want to use Naruto's immortality for their own evil purposes.
Another plot could involve Naruto teaching Kim some of his ninja techniques due to his immortality and vast experience. In return, Kim shows Naruto how to use modern technology in combat. This exchange of skills could lead to them facing a threat that requires both their newfound abilities.
One idea could be a crossover where Naruto and Kim Possible team up to fight a common enemy from both their worlds. Maybe a villain who has the ability to steal ninjutsu and use it against the world, and also has high - tech gadgets to cause chaos like Drakken would.
Another interesting concept is that there is a threat that only their combined worlds' powers can defeat. So, a group of villains from Naruto's world are using some high - tech devices stolen from Kim's world to create chaos. Naruto and Kim, along with their respective friends like Ron and Sakura, have to work together to figure out how to stop them.
In this 'Kim Possible Kidnapped Fanfiction', there could be a scenario where Kim is kidnapped while on a mission in a foreign country. The kidnappers could be local criminals who mistake her for someone else. Or maybe a mad scientist kidnaps her to use her as a test subject for his dangerous experiments. Another plot could involve a group of ninjas kidnapping Kim as part of a long - standing feud with her family's martial arts legacy.
One idea could be an OC who is a new villain in Middleton. This OC could have a unique power like the ability to manipulate technology remotely. They start causing chaos by hacking into all the city's systems. Another idea is an OC that is a long - lost relative of Kim and comes to live with her family. This OC has a different set of skills and gets involved in Kim's missions in unexpected ways. Or perhaps an OC who is an alien exchange student at Kim's school and has to hide their true identity while also helping Kim fight off intergalactic threats.
Another interesting concept could be a story where Naruto visits Kim's world on a mission and has to adapt to the different rules and technology there while still using his ninja skills. He could end up helping Kim on one of her missions in a unique way. For example, using his shadow clone jutsu to create multiple distractions while Kim sneaks in to retrieve an important item.
One plot idea could be their adventures as a married couple fighting villains together. Maybe they have to deal with a new super - powered enemy while also juggling their married life, like who does the dishes when they come back from a mission. Another idea is that they go on a honeymoon that turns into a mission to save the world.
One idea could be that Danny and Kim have to team up to stop a new villain who has the power to manipulate time. This would put both their skills to the test as they race against the clock. Another plot could involve a ghostly artifact that Kim discovers during one of her missions, and she has to call on Danny's expertise in the supernatural to figure out what it is and how to deal with it.
One idea could be a story where Ron accidentally discovers a new power and Shego, instead of being an enemy, decides to help him control it because she's intrigued. Meanwhile, Kim is a bit suspicious of their newfound alliance.
One idea could be that Jim and Tim create a new invention that accidentally causes chaos in Kim's crime - fighting world. For example, it might disrupt her communication devices during an important mission.
Another plot could involve Harry Potter visiting Kim's world. He'd be amazed by all the high - tech gadgets. Kim and her friends could introduce Harry to the concept of global crime - fighting on a non - magical level. Harry, in turn, could show them some basic magic tricks, and together they could stop a villain who's trying to steal both magical and technological secrets.