It is a somewhat popular theme among those who enjoy exploring alternative relationships in fanfiction. Inuyasha has a large and diverse fan base, and for some, the idea of Kagome and Naraku in a love relationship offers a fresh take on the story. It allows for a deeper exploration of character motives and emotions that might not be as fully developed in the original series. This type of fanfiction can also bring out new aspects of the Inuyasha universe, like how the relationship could potentially change the overall plot or the other characters' reactions.
Inuyasha would also be worried about Kagome's safety. He knows how devious Naraku can be. He might call out to Kagome as he gets closer to Naraku's lair, hoping to hear her voice and know that she's still alive. His reaction would be a mix of anger, worry, and determination to rescue the woman he loves.
One idea could be a scenario where Inuyasha and Naraku are forced to team up against a greater evil. Maybe a powerful demon from another realm arrives and threatens to destroy everything they both hold dear. They start off distrusting each other but gradually learn to work together as they realize they have no other choice.
You can make it unique by exploring different character aspects. For example, delving deeper into Naraku's past and how it could have made him different. Or showing a side of Inuyasha that we haven't seen much in the original, like his diplomatic skills when dealing with other demons.
One idea could be a story where Inuyasha and Naraku are forced to team up against a greater evil. They start off distrusting each other but gradually come to understand each other's motives. Another could be a what - if scenario where Naraku was redeemed early on and had to work with Inuyasha to protect the Shikon Jewel from a new threat.
You can start by giving them a common goal. For instance, if there's a threat to the world of feudal Japan that only they can stop together. This would force them to interact and gradually build some sort of understanding.
One interesting plot idea could be a time - travel scenario where Inuyasha and Naraku are sent back in time before all their enmity began. They might end up having to work together to survive in that time period, and in the process, they start to understand each other better. Maybe they even form an unlikely friendship that changes the course of their future relationship.
The plot could involve them being brought together by some sort of magical force. Maybe a powerful artifact needs to be protected, and they are the only ones who can do it because of their unique bloodlines. As they spend time together, they start to fall in love. However, they face a lot of opposition from both sides. The friends of Inuyasha's son think he's betraying his father's memory, and Naraku's old minions might try to use the daughter for their own evil plans.
Their relationship could develop through acts of kindness. Maybe Naraku's daughter saves Inuyasha's son from a dangerous demon. This would make him see her in a new light. And she, on the other hand, might be attracted to his sense of justice and honor, which is very different from her father. As time goes on, they would start to communicate more deeply, sharing their hopes and fears, and slowly falling in love despite the odds.
In fanfiction, the relationship between Kagome and Naraku can be very complex. Some fanfictions might explore the idea of Naraku having unexpected feelings for Kagome or vice versa. It could be a way to rewrite their antagonistic relationship in the original work and give it a new twist.