In such a fanfiction, Harry might be used as a bait to lure his friends into a trap. Voldemort could try to extract information from Harry about the Order of the Phoenix or Dumbledore's plans. Maybe he would also attempt to turn Harry to the dark side by showing him the so - called 'power' of the Dark Arts.
Well, Harry could find himself in a really tough situation. He might be held in some dark and dreary place, like the Malfoy Manor's dungeon. Voldemort may subject him to various forms of mental torture, trying to break his spirit. And his friends, like Hermione and Ron, would surely be desperate to rescue him, leading to a series of dangerous and exciting rescue attempts.
In a 'l gets kidnapped fanfiction', there could be a lot of drama. Maybe his friends would start a search mission right away. They might follow some small clues like a piece of cloth from his clothes left at the scene.
Well, his friends might launch a rescue mission. They would use their various skills to track down where Kakashi is being held. Naruto could use his shadow clones to search different areas, while Sasuke might use his Sharingan to detect any hidden threats on the way to the rescue.
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, perhaps there would be a heroic rescue attempt by her family. They would use their unique powers to track her down.
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.
If Voldemort gets custody of Harry in fanfiction, it would be a huge deviation from the original story. Harry would probably be exposed to a lot of dark and cruel things. Voldemort could try to break Harry's spirit and make him abandon his values. There might be a struggle within Harry between the good he has been taught and the evil that Voldemort represents. And the wizarding world would be in even more chaos as Voldemort would have more control over the one person who was seen as the hope to defeat him.
In such a fanfiction, perhaps Charlie's brothers would use their skills to track him down. Donnie might use his technological know - how to analyze any digital trails left by the kidnappers. Meanwhile, Alan could provide moral support and also help by recalling any details about people who might have a grudge against Charlie.