To develop the Sound Spy character, start with their motivation. If they are spying for power, show how that desire for power grew over time. Their relationships with other characters are also important. They could have a mentor in the Sound Village who taught them everything about spying. And don't forget about their appearance. Give them some distinct features that are related to their sound - based abilities, like ears that are more sensitive to certain frequencies.
The Sound Spy's character can be developed by giving them a unique fighting style. For example, they could use sound - based jutsus in a very creative way, like creating illusions through sound vibrations. Also, their backstory is crucial. Maybe they were forced into spying for the Sound Village due to a threat against their family.
One plot idea could be that the Sound Spy has the ability to copy not just jutsus like a certain Uchiha, but also the emotions and memories associated with them. This could lead to some really complex character interactions within the Naruto universe. Another idea is that the Sound Spy is actually a double agent working for Konoha all along, and their mission is to expose Orochimaru's true plans from the inside of the Sound Village.
One way is to describe the sound in detail. For instance, if it's a creaking noise in an old, haunted house fanfic, you can write about how it starts softly and then grows louder, adding to the sense of chaos among the characters who are already on edge. Then show how the characters react to it, whether they investigate or run away in fear.
On the spy mission, their relationship is bound to evolve. The secrecy and danger of the mission create an environment where they have no one else to turn to but each other. Hinata, with her shy nature, might start to become more confident around Naruto as they work side by side. Naruto, on the other hand, will notice Hinata's intelligence and courage more. They might have quiet moments during the mission, perhaps hiding from enemies in a small space, where they share their hopes and dreams for the future. These shared moments will strengthen their bond, and they may even start to fall in love more deeply as they see each other in new and different lights during the spy mission.
If Naruto joined Sound in a fanfic, it would completely change the Naruto universe. His relationships would be flipped. Instead of being with Konoha friends like Sasuke and Sakura, he'd be among Sound ninjas. His training might take a different turn too, perhaps learning more brutal and underhanded techniques. This could also lead to a different set of battles and power dynamics in the story.
In 'A Sound of Thunder', the characters are developed in a very interesting way. Eckels, at the start, is full of bravado, talking about how he wants to hunt a dinosaur. But as soon as he is in the prehistoric jungle, his true nature emerges. His body language, like his cowering, and his stuttering words show his transformation from a confident man to a scared one. Travis is developed through his consistent enforcement of the rules. Every time he scolds Eckels or gives instructions, we learn more about his character. Lesperance, too, is developed as he tries to balance the situation. His attempts to calm Eckels down and his explanations about the time - travel mechanics all contribute to his character development.
In a fanfic where Naruto joins Sound, his relationships would be in turmoil. His friends in Konoha would see him as a traitor. Naruto would have to build new relationships within Sound. He could befriend some of the more misunderstood Sound ninjas. Also, the story could explore how Naruto's presence in Sound affects the power balance between the villages. It could lead to new alliances and rivalries, and the overall tone of the Naruto story would become much darker and more morally ambiguous.
You can find 'sound Naruto fanfic' on fanfiction.net. It has a large collection of Naruto - related fanfictions, and you can easily search for ones related to the Sound Village or characters from there. Just use the search bar and type in relevant keywords like 'Sound Village' or 'Sound ninja' along with 'Naruto'.
One way could be to use the idea of 'freedom' in the Naruto context. For example, the shinobi in Naruto are often restricted by their village rules and missions. A fanfic could explore a character's journey to break free from these constraints in a way similar to the concept in 'The Sound of Freedom'.
One potential consequence could be that his body experiences a great deal of strain. Breaking the sound barrier means extreme speed, and this could put a huge amount of stress on his muscles, bones, and internal organs. He might need time to recover and adjust to the new physical limits he has reached.
I'm not sure specifically as there could be many different interpretations of a 'Naruto Sound of Love' fanfic. It might be a fan - created story that focuses on a romantic relationship within the Naruto universe, perhaps involving characters from the Sound Village and themes of love.