If we consider this 'kai has kidnapped bonnie fanfiction', it could lead to a complex relationship development. Kai might start to have second thoughts about his actions as he spends more time with Bonnie. Meanwhile, Bonnie could be secretly planning her escape while pretending to be compliant, all while the readers are on the edge of their seats waiting to see what will happen next.
Her friends, like Damon and Stefan, might come to her rescue. They are often the ones to jump into action when one of their own is in danger.
If Kai is kidnapped in a fanfiction, it could be that the kidnappers are after his power of fire. They might try to extract it from him or use him as a bargaining chip against the other ninjas. The story could then revolve around how Kai resists their attempts while waiting for his friends to save him.
In such a fanfiction, Naruto's friends would likely go on a desperate search for him. Sasuke might put aside his pride and team up with the others. They would follow any leads, like tracking the kidnapper's chakra signature if possible.
If Naruto is kidnapped by Kumo in fanfiction, it could lead to a series of intense battles. Naruto himself might try to escape on his own using his ninja skills and the power of the Nine - Tails. His captors in Kumo would probably want to extract some sort of information from him, like the secrets of the Nine - Tails or Konoha's defense strategies. However, Naruto is a tough character and would surely put up a fight.
Well, in this kind of fanfiction, usually the main character might be in a state of fear at first. They could be held in a spooky castle or lair of the vampire prince. Maybe they would try to escape but find it difficult due to the vampire's powers and the unfamiliar surroundings.
In fanfiction, if Deku gets kidnapped, his friends from U.A. High would likely launch a rescue mission. Bakugo might be especially determined, as much as he tries to hide his concern. They would use their quirks in creative ways to track Deku down.
In the 'sonic is kidnapped by scourge fanfiction', Sonic's friends would surely be worried sick. Tails might start using his gadgets to track Sonic down. Meanwhile, Sonic himself would be constantly thinking of a way out. Scourge could have kidnapped him for various reasons, like to prove he's stronger or to get some sort of information from Sonic. Sonic would not go down without a fight though, and he'd be looking for any opportunity to break free and foil Scourge's plans.
In a Destiel - centered fanfiction where Sam is kidnapped, perhaps it's all part of some grand scheme to make Dean realize his true feelings for Cas. The kidnappers might be some over - zealous fans within the story who think that by causing chaos, they can bring about the Destiel endgame. They could hold Sam in some strange, other - dimensional location and send Dean and Cas on a quest to find him.
In the 'tsuna gets kidnapped fanfiction', perhaps his friends would immediately start a rescue mission. They might use their unique skills and powers to track down where Tsuna is being held.
In this kind of fanfiction, perhaps Hiccup would be in great danger. Drago might use Hiccup as a hostage to get something he wants, like controlling the dragons that are allied with Hiccup's people. He could also try to force Hiccup to reveal the secrets of his unique bond with Toothless.