Who are the best characters to include in Saiki x Kaidou fanfiction besides them?

Nendo could be a great addition. His simple - minded yet loyal nature can add some humor and unexpected twists. For example, he might accidentally almost expose Saiki's powers while trying to be helpful in a situation involving Teruhashi.

Lapis Lazuli could be a great addition. She has a complex relationship with Peridot, and her presence could add some drama and depth. For example, she might be initially suspicious of Steven and Peridot's friendship, thinking that Steven is influencing Peridot too much. But over time, she could come to see the positive aspects of their bond.

Jimmy Olsen could also be a great character to include. He is Superman's friend and colleague at the Daily Planet. His loyalty and his ability to get into some sticky situations can add a touch of humor and also some interesting sub - plots to the Supergirl and Superman fanfiction.

Master Roshi could also be a great addition. His old - school ways and his comical reactions to Vegeta and Bulma's relationship can be really entertaining. For instance, he could give some really strange relationship advice to Vegeta based on his own limited understanding of modern relationships.

Meiko would be a great addition. She could act as a mentor figure to Miku and Luka, with her more mature and experienced personality in the virtual idol world. Kaito could also be included, perhaps as a friendly rival to both Miku and Luka in music competitions. He could bring a different style of music and a bit of humor to the story.

Metro Man could be a great addition. His presence could add some tension or an interesting dynamic, especially considering his past relationship with Megamind. Minion, Megamind's loyal sidekick, is also a must - include. He could provide comic relief and his unique perspective on Megamind and Roxanne's relationship. And maybe the Warden, who could be involved in some sort of prison - related subplot or just add to the overall chaos in the story.

Sasuke could be a great addition. He might initially be skeptical of Naruko's newfound bond with the Kyuubi, but then come to see the potential in it. Kakashi could also be included as he has a lot of knowledge and experience. He could offer guidance to Naruko on how to handle the Kyuubi's power. Another good character would be Jiraiya. He could have some interesting insights into the relationship between Naruko and the Kyuubi, having known about the Kyuubi for a long time.

The King and Queen of the kingdom. Their presence can bring in the political and parental aspects. They might have different views on how Rapunzel and Cassandra should handle certain situations, which could create more conflict and plot twists.

Another plot could involve Kaidou finding out about Saiki's powers by accident. At first, he's in shock but then realizes they can use these powers for good, like helping the school win a big competition against a rival school. They start training together in a comical way, with Kaidou trying to come up with strategies that work with Saiki's powers.

Well, one character that would be interesting to include is Commissioner Barbara Gordon. She has a long history with the Batman universe and can serve as a link between the old and new. In addition, Brother Eye could be a great addition. It's a powerful and complex entity that can create all sorts of plot twists. And don't forget about Inque. Her shape - shifting abilities can make for some really exciting and unpredictable story elements when combined with Batman and Barda's story.