In some fanfictions, it could be an unknown alien species. They might have detected Bumblebee's unique energy signature and decided to take him to study his technology or abilities. This could lead to all sorts of interesting adventures as Bumblebee tries to communicate with them and find a way to escape.
One idea could be that Bumblebee is taken by a group of Decepticons who plan to reprogram him. Another could be that he's taken by a secret human organization for study. Maybe he's taken by a powerful alien race to use his abilities for their own purposes.
One possible plot could be that a group of evil Decepticons steal Bumblebee because they know he has some valuable information stored in his memory banks. The Autobots then launch a rescue mission to get him back. They might face various challenges and battles along the way.
In such a fanfiction scenario, first of all, the Volturi would likely have their reasons for taking Renesmee, perhaps believing she is a threat to the vampire world order. Once taken, the Cullens would be desperate. Alice might use her visions to try to find Renesmee's location. Jacob could also play a crucial role as he has a special bond with Renesmee. He may attempt to lead a rescue mission or at least try to communicate with her while she is in the Volturi's custody. The story would be filled with drama, action, and the exploration of relationships between different characters in the 'Twilight' universe.
In the 'ponyboy gets taken by a demon' fanfiction, a lot can unfold. First, the demon might have been observing ponyboy for a while, waiting for the right moment to strike. Once taken, ponyboy could be exposed to all kinds of strange and terrifying things in the demon's world. He might meet other captives or creatures there. He would have to rely on his wits and any latent courage he has. There could also be a chance that he discovers some sort of connection between himself and the demon's world that he never knew before, which could either help him escape or make his situation even more complicated.
His friends might be able to save him. If they notice his disappearance quickly enough, they could band together and search for him. Maybe they have some knowledge or items that can be used against the demon.
Definitely the Cullens, especially Bella and Edward as Renesmee's parents. Also, Jacob who has a strong connection to Renesmee. And of course, the Volturi leaders like Aro, Caius and Marcus.
In a fanfiction where Sam gets taken hostage in the Flashpoint universe, it could lead to many different scenarios. One possibility is that the other characters, like Barry, would immediately go into rescue mode. They might use their super - powers or detective skills to track down Sam's location. For example, Barry could use his super - speed to search the city in a matter of minutes.
Well, it could be an alien race that has control over the rift and doesn't want Owen to be rescued. They might see him as a threat or an interesting specimen to study.