One interesting plot could be the baby having special powers due to its unique heritage. Since Bonnie is a powerful witch and Klaus is an Original vampire, their child might inherit a blend of magic and vampire abilities, like being able to use magic to enhance vampire speed or strength. Another plot could be the challenges they face in protecting the baby from the enemies they've made over the years. Enemies might see the baby as a threat or a valuable asset.
The baby could also have a special connection to the spirit world. Bonnie, with her witch powers, and Klaus, with his long and complex history, could find themselves on a journey to understand this connection. They might meet different spirits who either offer guidance or pose a danger to the baby as it grows up.
Perhaps a plot where the baby has some unique and unexpected powers. Bonnie and Enzo then have to figure out how to help the baby control these powers while also hiding them from those who might want to use the baby for their own gain. For example, other witches or vampires in their world could be interested in the baby's powers for various reasons. They would face a lot of challenges in this situation, like finding a safe place to live and training the baby in secret.
One great Klaus and Bonnie baby fanfiction could be about how they deal with the challenges of raising a baby in a world full of supernatural threats. Maybe they have to protect the baby from other vampires or witches who might see the child as a threat or a valuable asset.
One interesting plot could be the baby girl having unique powers inherited from Klaus. Maybe she can control the elements like fire or wind. This would create all sorts of adventures as Klaus and Caroline try to protect her from those who might want to use her powers for their own gain.
The main characters are Bonnie, a witch with great power and a kind heart deep down. Klaus, an Original vampire who is both feared and respected in the supernatural world. Their baby is also a main character, which is the focus of the fanfiction. There might also be other supporting characters like Damon and Stefan from the Vampire Diaries universe who could interact with Bonnie and Klaus regarding the baby. They might be curious, or they might be worried about the implications of this new addition to the supernatural world.
You can try searching on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions from various fandoms, including ones related to Klaus and Bonnie. Just type in 'Klaus and Bonnie baby' in the search bar, and it should show you relevant stories.
Elijah could be on their side. He is Klaus' brother and might understand the importance of the baby, especially if he sees it as a way to keep Klaus in line or to bring about a new era of peace among the different supernatural species. He could use his diplomatic skills to protect the baby from threats.
Well, a possible plot could be that they marry as a political move in the supernatural world. Klaus, being a powerful vampire, and Bonnie, a strong witch, their union could shift the power balance. Then, they might face challenges from other supernatural factions who oppose their union. Also, a plot where they get married due to a magical bond that was accidentally created, and they have to figure out how to make their relationship work while dealing with their own personal issues and the reactions of their families and friends.
One plot idea could be that Bonnie and Klaus travel back to a time when the Original family was first created. They could witness the making of the first vampires and how it all started. This would give them a chance to change certain things that might affect the present they come from.
One interesting story could be about the baby's unique powers emerging early and how Klaus and Hayley deal with protecting the baby from those who would misuse its powers. They might have to seek out allies in the supernatural community and face many challenges along the way.