Their relationship would likely become more protective. Arthur would be more vigilant about Mera's safety and well - being, always making sure she is comfortable and secure.
One possible plot twist could be that the pregnancy is not as straightforward as it seems. Maybe there are some magical or otherworldly elements affecting the baby's development. For example, an ancient curse might be influencing the unborn child.
Since we have no details about the story, it could be a legend passed down in Atlantis. Maybe it's a story about a great hero from their past, and Mera is telling Arthur this story to inspire him or to give him some historical context that could be relevant to their current situation. It could also be a story about the magic or unique powers that exist in their world, which Arthur may need to understand better for some future task or challenge.
She might tell Arthur the story to make him understand something better. For example, if it's a story about Atlantis' history, she could be trying to make him more aware of his heritage and the significance of his role in their world. Or it could be a story of a past mistake that she doesn't want Arthur to repeat.
One great 'Aquaman Arthur and Mera Fanfic' is 'The Depths of Their Love'. It beautifully explores the relationship between Arthur and Mera. The author does an amazing job of delving into their characters, showing how they support each other through the various challenges in Atlantis. It's filled with vivid descriptions of the underwater world and their adventures together.
One idea could be a story where Arthur and Mera go on an adventure to a hidden underwater kingdom that has been forgotten by most. They could face challenges like ancient sea creatures and mysterious magic.
The writing style also matters. If the author can create a vivid and immersive world, it will draw the readers in. Using descriptive language to portray the underwater kingdom, the powers of Arthur and Mera, and their emotions towards each other will make for an excellent fanfic.
He could be overjoyed if he believes the child is his. He would see it as a continuation of his lineage and a sign of their love. He might start making plans for the child's future, like ensuring the best education and training in Camelot.
On Archive of Our Own (AO3), there are likely some great Arthur Mera fanfic authors. You can search for their stories and then check out the other works by the writers who create engaging stories about them.
One great Merlin and Arthur pregnant fanfiction is 'The Unlikely Miracle'. It's really interesting as it explores how the Camelot court reacts to such an unexpected situation. The author does a wonderful job of staying true to the characters' personalities from the original series.