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 thing that could happen is that Keiko tries to talk her way out of the situation. She could try to appeal to Karasa's sense of humanity or reason. For example, she might say that she has a family who will be worried about her or that Karasa will get into a lot of trouble if he doesn't let her go.
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.
In one scenario, Hiei might kidnap Keiko to use her as bait to draw out Yusuke. He could be forced by some powerful enemy who wants to get revenge on Yusuke. Hiei, being a rather complex character, might not be entirely happy about this but feels he has no choice. He would keep Keiko in a hidden location, perhaps in the demon world where it's hard for Yusuke to reach easily.
One possible plot could be that Rando is a jealous rival of someone close to Keiko. He kidnaps her to try and force her into a relationship with him. Keiko, being a strong - willed character, tries to outwit Rando at every turn during her captivity.
Another plotline might involve Karasu having a personal vendetta against Keiko or someone close to her. He kidnaps her to exact revenge in a more elaborate and drawn - out way. This could lead to a series of events where Keiko tries to outwit Karasu and escape while also uncovering the true reasons behind his actions. And during this process, there could be unexpected alliances and betrayals.
Yusuke would be extremely angry. He would immediately start looking for Keiko. Yusuke is very protective of her, so he would drop whatever he was doing and go on a full - scale search. He might first try to find Hiei's usual hiding places in the demon world and question any demons he comes across.
Finding 'karasu kidnaps keiko fanfiction' can be a bit of a hunt. You could also try using more general search engines. Enter the exact phrase 'karasu kidnaps keiko fanfiction' along with keywords like'read' or 'fan - made stories'. But keep in mind that the availability of such specific fanfiction depends on how popular the concept is within the fan community.
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.