There could also be some unexpected characters who come to the rescue. Maybe some powerful spirits who have a debt to Yusuke or who just can't stand Toguro's evil deeds might show up to save Keiko and thwart Toguro's plan.
His friends like Kuwabara and Kurama might also join in the rescue. Kuwabara with his tough fighting spirit and Kurama with his cunning and powerful abilities could be a great help in getting Keiko back from Toguro.
Yusuke could use his spirit detective skills to track down Keiko. He might fight his way through Sakyo and Toguro's minions to reach her.
In such a fanfiction, perhaps Toguro kidnaps Keiko to use her as bait to lure Yusuke. He might think that Yusuke will come to rescue her no matter what, and then he can have a rematch with Yusuke on his own terms.
Well, perhaps in this fanfiction, Sakyo and Toguro kidnap Keiko because they think she has some special power or knowledge. Maybe they believe she can lead them to a powerful artifact. Keiko, being a strong - willed character, tries to resist them and find a way to escape. Meanwhile, her friends are desperately searching for her, and they end up having to team up with some unexpected allies to take on Sakyo and Toguro.
One possible character could be Keiko's father. He is a powerful and influential man in their community. When he finds out about Keiko's kidnapping, he uses all of his resources, including his connections with the local police and his own private security force, to try and rescue her. Then there could be a detective, Inspector Kenji, who is assigned to the case. He has a reputation for being tenacious and smart, and he starts to piece together the clues about Rando's identity and motives.
One possible plot could be that Keiko is caught in the crossfire of a demon battle that Yusuke is involved in. Yusuke, being a spirit detective, has many enemies. Maybe a powerful demon targets Keiko to get back at Yusuke. After her death, Yusuke could go into a deep state of despair and vow revenge. He might journey to the spirit world to find a way to bring her back, facing numerous challenges along the way.
Yusuke would likely become more withdrawn. He was always a bit of a rough - around - the - edges character, but Keiko's death would make him more somber. He might lose his sense of humor that he sometimes showed around her.
If Karasa kidnaps Keiko in a fanfiction, the story could go in many directions. For instance, Keiko might turn out to be much stronger than Karasa expected. She could use her wits and any special abilities she has to try and escape. Or perhaps there are other characters who will come to Keiko's rescue. They could be friends, family, or even strangers who happen to be in the right place at the right time.
One way the story could develop is that Yusuke goes into a deep state of grief and denial at first. He might start to isolate himself from his friends and the spirit world as well. He could be haunted by memories of Keiko and constantly wonder if there was something he could have done to prevent her death.
Keiko in the Free Willy story was an orca that was living in captivity. He was the focus of the story because his situation made people think about the ethics of keeping such intelligent and large animals in captivity. His presence in the movies made him well - known, and that popularity led to a movement to try and return him to his natural habitat.
Maybe Pepper Potts could find out what Tony has done and rescue Peter. She might be able to talk some sense into Tony and make him release Peter.