In a Zero and Ichiru fanfiction, Senri could be an interesting character to add. He is often paired with Rima, and his laid - back attitude could be a nice counterpoint to the intensity of Zero and Ichiru. Also, Maria Kurenai could be included. She has her own story and powers, and her interactions with Zero and Ichiru could lead to new plot developments. Moreover, the addition of Kain Akatsuki would be good. His loyalty to the vampire hierarchy and his friendship with Aidou could add more layers to the relationships and power dynamics in the fanfiction.
Yuki could be a great addition. She has a strong connection to Zero already, and her presence could add an interesting dynamic to the relationship between Zero and Ichiru. Also, Kaname. Since he is such a central figure in the Vampire Knight world, his interactions with Zero and Ichiru could create a lot of tension and drama. Another character could be Aidou. His flamboyant personality could provide some comical relief in an otherwise intense story.
I think Ruka would be a good character to include. She has her own feelings towards Kaname and is often involved in the power plays within the vampire community. Her presence could bring in more of the vampire politics into the fanfiction. Then there's Shiki. His quiet and somewhat mysterious nature could contrast well with the more volatile personalities of Zero and Ichiru. And don't forget about Headmaster Cross. He has a lot of knowledge about vampires and could serve as a mentor or a source of information for Zero and Ichiru in the fanfiction.
One possible aspect of this fanfiction could be the complex relationship between Zero and Ichiru. In the Vampire Knight universe, they have a very strained brotherly bond. In fanfiction, authors might explore how to heal that bond or what could have been different in their relationship if certain events hadn't occurred.
Attention to detail in the Vampire Knight lore is also important. This includes things like the vampire hierarchy, the rules of the academy, and the history of the vampire - hunter families. By adhering to and expanding on this lore, the fanfiction can feel more like an authentic part of the Vampire Knight world.
A great plot for a Vampire Knight Zero and Ichiru fanfiction could be set in an alternate universe. In this universe, they were never separated by the circumstances in the original story. They grow up together as normal brothers, without the knowledge of vampires. However, as they get older, they start to notice strange things happening around them. Eventually, they discover the existence of vampires and have to decide whether to fight them or join them. This story could explore their bond in a completely new context and show how they would react to this new world compared to their counterparts in the original story.
Axl can be a great addition. He has his own unique abilities and a bit of a wilder personality compared to X and Zero, which can add some interesting dynamics. Also, Sigma is often included as a major antagonist. His complex motives and powerful presence make for great story material. Another good character is Alia. She can provide support to X and Zero from the base, and her intelligence can be used in various ways in the fanfiction, like helping to analyze enemy weaknesses.
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.
Nendo could be a great addition. His simple - minded nature can add a lot of humor. For example, he could misunderstand the relationship between Saiki and Kaidou and try to get in on their 'adventures' in a really clumsy way.
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.
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.