The 'haise sasaki x saiko fanfiction' might also focus on the emotional bond between them. It could explore themes like trust, loyalty, and love. Perhaps there are scenes where they have to rely on each other's emotional support in difficult situations, which deepens their connection.
One common theme could be friendship. They might start as friends and their relationship gradually evolves. Another theme could be the struggle against a common enemy. This would bring them closer together as they fight side by side.
One challenge could be the difference in their personalities. Haise is more reserved and Mutsuki can be quite intense. This could lead to conflicts within their partnership, like misunderstandings during missions. Another challenge might be their loyalty to the CCG. If they start to question the CCG's motives, they would have to decide whether to stay loyal or follow their own moral compass. For example, if the CCG orders them to do something unethical.
One idea could be a story where Haise Sasaki and Mutsuki are on a mission together and they encounter a powerful ghoul. They have to rely on each other's skills to survive. Haise uses his detective skills to analyze the ghoul's behavior while Mutsuki uses his combat abilities. Another plot could be a character - development - focused story where Mutsuki is having doubts about his place in the CCG and Haise helps him through it, sharing his own experiences of identity struggle.
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.