Well, it could be that the kidnapper has some ulterior motives related to Renesmee's special nature. Maybe they want to study her or use her powers for their own evil plans. Her friends and family would then have to figure out who the kidnapper is and what they want in order to get her back safely. They might face many challenges and obstacles along the way, like false leads or traps set by the kidnapper.
In such a fanfiction, perhaps there would be a heroic rescue attempt by her family. They would use their unique powers to track her down.
Maybe a human who has discovered the existence of vampires and wants to use Renesmee to prove it to the world. They might think that by kidnapping her, they can expose the vampire world and gain fame or fortune. Another option is a rogue werewolf who doesn't like the alliance between the vampires and werewolves and decides to take Renesmee as a way to break that bond.
In such a fanfiction, Goku might be kidnapped by a powerful new villain. His friends would then start a search mission. Maybe Vegeta would be the first to volunteer, thinking it's his chance to prove he's stronger than Goku.
In the 'ichigo gets kidnapped fanfiction', he might be rescued by his friends. For example, his comrades from the Soul Society could sense his distress and come to his aid.
In the 'darkrai gets kidnapped fanfiction', perhaps a group of trainers who want to control the power of the Legendary Pokémon Darkrai kidnapped it. They might be planning to force Darkrai to battle other Legendaries. This would create a lot of chaos in the Pokémon world as Darkrai is a very powerful and mysterious Pokémon.
In such a fanfiction, Tails might be kidnapped by an old enemy like Dr. Eggman. His friends, like Sonic, would then start a rescue mission. They would search all over the place, from the Green Hill Zone to Eggman's secret bases.
Well, in the fanfiction, Gengar might be held captive by some powerful villains who want to use its powers for their own evil plans. Maybe they'll try to force Gengar to haunt a particular place or to attack someone. The Pokémon trainers in the story could then start a rescue mission to save Gengar.
Another scenario could be that the kidnappers have some sort of ulterior motive related to Sora's special powers. They might try to extract that power from him, but Sora, being the strong - willed character he is, would fight back in some way, even while being held captive.
Perhaps she'll use her own abilities to escape. Sarada is a strong and intelligent ninja. She could outwit the kidnappers, find a weakness in their security, and make a run for it. For example, she could use her Sharingan to deceive them or find a hidden passage if she's locked in a room.
Well, perhaps Pikachu would go on a heroic quest to rescue Ash. It might team up with other Pokémon like Charizard. They could follow the kidnappers' trail, facing various challenges along the way, like battling wild Pokémon or getting through difficult terrains.
In the 'rose gets kidnapped by the master fanfiction', it might be that the master kidnapped Rose to force her into doing something against her will. For example, he could be a villain in a magical world and wants Rose to use her special powers for his own dark purposes. Her kidnapper could be holding her in a hidden lair, which is full of strange and dangerous things. There might be a long and drawn - out struggle between Rose trying to free herself and the master trying to keep her under his control. This could involve a lot of psychological warfare as well as physical confrontations, depending on the nature of the fanfiction.