A fanfic could focus on a what - if scenario. What if Tomoya had met Nagisa earlier in their lives? Maybe they would have formed an even deeper bond from a younger age. They could have shared more childhood memories and their relationship might have developed in a different, yet equally beautiful way.
Yes, there are likely fanfictions out there with such a concept. The Naruto fandom is vast and creative, and crossovers with historical or other fictional characters like Sasaki Kojiro are not unheard of. Some fans might be intrigued by the idea of Naruto having some sort of connection or admiration for Sasaki Kojiro and create stories based on it.
A simple adventure - based fanfic could be where Tomoya and Nagisa decide to go on a road trip. Along the way, they discover new places, meet interesting people, and have heart - to - heart conversations that strengthen their relationship. They might even encounter some small challenges like getting lost or having car trouble, but they always get through it together.
Tomoya survives in Clannad After Story. The series takes the characters through various challenges and emotional arcs, but he makes it through to the end.
Hey, let me recommend a Doujinshi novel by Go Soul to you. It's called Go Soul: Onmyoji System." The novel was mainly about a person named Light who transmigrated to the world of Go Soul and met his childhood sweetheart, Fujiwara Sasaki. The two of them went through many hardships together and finally got together. The author of this book was Jun Wushang, and the quality was quite good! I hope you like my recommendation. Muah ~