Yes, there might be some. Fanfiction is a vast world where different universes can be mashed up. Writers often like to combine characters from different series, like Naruto and Roy Mustang from Fullmetal Alchemist. You can try searching on popular fanfiction websites.
At first, Edward might be a bit resistant to Roy's attempts at adoption. But as time goes on, Roy shows his care and concern for Edward. He helps Edward with his problems, like dealing with the homunculi or his own self - doubt. Edward then starts to rely on Roy more, and their relationship deepens into a strong bond of family - like love.
I'm not sure if there is a specific 'Harry Potter is Roy Mustang fanfiction' out there. These are two very different fictional universes, so it would be a rather strange and creative crossover. You might have to do a very thorough search on various fanfiction platforms to find out.
One common theme is power and ambition. Since Roy Mustang is a character associated with power (his fire alchemy) and his ambition to rise in the military, many OCs are created to either complement or contrast with that. For example, an OC might have a power that can either enhance or hinder Mustang's own power, and their interactions revolve around how they deal with power dynamics.
One great 'Edward Elric Roy Mustang Fanfiction' is 'The Alchemist's Bond'. It beautifully weaves the relationship between Edward and Roy Mustang. The story has an engaging plot where they have to team up against a new threat in the world of alchemy. The characterizations are on point, staying true to their original personalities from the series.
Female Roy Mustang fanfiction is unique because it can offer a fresh take on his character. For instance, it could explore his vulnerability from a female perspective, which might not be as prominent in the main story. It can also create unique relationships between him and female characters, whether it's a friendship, a mentorship, or a romantic relationship. These fanfictions can also delve into how his actions and decisions impact female characters in ways that add depth to the overall story.
Maybe Naruto could be transported to the Fullmetal Alchemist world and learn alchemy from Roy Mustang. He could use his ninja skills along with alchemy to fight enemies in that world.
One great 'Edward Elric and Roy Mustang Fanfiction' is 'The Alchemist's Path'. It delves deep into their relationship as they work together on a dangerous mission. The story shows how their different personalities, Edward's impulsiveness and Roy's calculating nature, complement each other. Another good one is 'Flames of Brotherhood'. It focuses on how they gradually come to respect and trust each other more over time. There are some really heart - warming moments in it.
There's this fanfiction called 'Flames and Metal'. It shows how Roy and Edward, with their different skills and personalities, learn to rely on each other. It has a lot of action scenes that are really exciting and it also develops their friendship in a unique way.
One great 'Roy Mustang x Reader Fanfiction' is 'Flames of Attraction'. It has a really engaging plot where the reader character gets involved in Roy's military operations in a very natural way. The chemistry between them is well - written.