Redemption is a common theme. Given the nature of the original story, many fanfics explore how characters continue to seek redemption for their past actions. For example, Shoya's journey of making up for his bullying past.
A fanfic could center around a trip they take together. They could go to a beautiful beach. Shouko would be excited to see the ocean for the first time, and Shouya would be there to make sure she has a great time. They might build sandcastles and collect seashells, and this simple trip could strengthen their relationship even more.
In a fanfic, their relationship could also take a more romantic turn. Ishida, who has come a long way from his bullying days, might start to see Nishimiya in a new light. He could realize his true feelings for her as they spend more time together, perhaps helping each other with their personal growth and insecurities.
A great Silent Voice fanfic idea could be a time - skip story. Imagine what the characters' lives are like years after the events of the movie. Have Shoya and Shoko stayed together? What about their careers? Maybe Shoya has become a sign language teacher, and Shoko is an artist. Or perhaps write a fanfic where a new character enters their lives, someone who doesn't know about their past but slowly uncovers it and helps them heal old wounds in new ways. You could also do a fanfic that's centered around the school events but with a magical twist, like a magical object that helps Shoko communicate more easily and changes the dynamics between the characters.
Definitely! 'A Silent Voice' manga has a powerful plot, beautiful illustrations, and it manages to convey complex emotions effectively. It's a must-read for manga lovers.