One plot idea could be that Snape kidnaps a student he suspects of being involved in a dark magic plot against Hogwarts. He wants to question the student privately to get to the bottom of it. Another could be that he kidnaps someone he believes has information about Voldemort's next move, thinking he can protect that person and extract the information at the same time. Or perhaps he kidnaps a character in a fit of jealousy or to protect them from a greater danger he foresees.
Well, in a fanfiction scenario where Snape kidnaps, it might be because he's trying to save someone from a false accusation. He takes them away to a secret location to prove their innocence. Maybe he kidnaps a person who has a special power that the Death Eaters are after, and he wants to keep them safe. It could also be that he's under some sort of spell himself that makes him believe kidnapping is the only way to achieve a certain goal, like retrieving a lost magical artifact.
In a Snape - kidnapping fanfiction, he could kidnap a character to force them to reveal the location of a hidden magical library. He might be desperate for knowledge that he believes only this character knows. Or, he kidnaps a person who has a connection to his past, perhaps someone who knew his family or has a secret about his early life at Hogwarts. He wants to keep this person close until he uncovers all the secrets. Additionally, he could kidnap someone who is unknowingly a key to a prophecy, and he needs to protect them from those who would use them for evil purposes.
Maybe Bucky kidnaps Steve because he believes it's the only way to protect him. There could be a new and powerful threat that Bucky has discovered, and he thinks that by taking Steve away from the public eye and the Avengers, he can keep Steve safe. But Steve doesn't understand Bucky's motives at first and there's a lot of tension between them until Bucky can explain.
Another plot could be that Alexis kidnaps Castle as a prank that goes too far. She initially just wanted to teach him a lesson about being overprotective or something, but then things spiral out of control. Realizing her mistake, she has to find a way to fix the situation without getting in too much trouble.
One idea could be that Magnus kidnaps a Shadowhunter to force them to reveal a secret that could save the Downworld. He might believe this Shadowhunter has crucial information that the Nephilim are hiding. Another could be that Magnus is being controlled by a dark force and kidnaps someone as part of its evil plan. Then, the kidnapped person's friends have to find a way to break the control on Magnus and save their friend.
One idea could be that the students are kidnapped by an unknown organization that wants to use their unique skills learned from Koro - sensei for some devious plan. The students then have to work together to escape while also trying to figure out the motives of their captors.
One plot idea could be that Draco kidnaps Hermione under the influence of a dark spell. He takes her to an old, abandoned manor. Hermione, being the intelligent witch she is, tries to find a way to break the spell on Draco while also trying to escape. She might start by using her knowledge of potions and magic to create a counter - spell.
Well, perhaps it's a case of mistaken identity. A new character in Riverdale is kidnapped instead of the intended target, who was thought to be Archie because of his popularity. This could lead to a series of events where the other characters have to race against time to find the kidnapped person before it's too late. They might discover new secrets about the town and its inhabitants during the search.
One plot idea could be that Marik Bakura is kidnapped by a group who wants to use his unique powers for their own dark purposes. They might try to force him to participate in some sort of dangerous ritual. Another idea is that he is kidnapped by someone who has a personal vendetta against him and plans to torture him psychologically. A third plot could involve a mistaken identity situation where he is kidnapped instead of someone else who looks similar, and then he has to figure out how to escape while also dealing with the kidnappers' confusion.
Well, perhaps in the fanfiction, they are all entered into a magical tournament. Harry, being the young and brave one, Snape with his vast knowledge of magic, and Lucius with his family's resources. At first, they are rivals in the tournament but then realize that there is an outside force trying to manipulate the outcome for evil purposes. So they join forces. Or it could be that a powerful dark magic spell has been cast over Hogwarts, and only the combined magic of Harry, Snape and Lucius can break it. They start off distrustful but as they work together, they form an unlikely alliance.
One plot idea could be that Snape takes Hermione under his wing after he discovers her extraordinary magical potential at a young age. He secretly trains her in advanced potions and dark arts defense, much to the surprise of the other Hogwarts faculty. Another could be that Hermione's parents die unexpectedly, and Snape, having a soft spot for her intelligence, steps in as a guardian. He helps her navigate the complex wizarding world politics while she tries to uphold her muggle - born values.
One idea could be that Harry punches Snape in a moment of extreme frustration after Snape makes yet another snide comment about his father. Then, Harry realizes the gravity of his actions and has to face the consequences within Hogwarts, which could lead to a series of adventures as he tries to make amends while also uncovering some long - hidden secrets about Snape's true motives.