The Titans' villains could also be involved in an interesting way. Slade, for instance, might try to use this discovery to his advantage, which would force Robin's friends to support him even more. But there could also be some villains who respect Robin more now that they know he's Red X. Additionally, any characters from Robin's past, like his old friends or trainers, could show up to either support or condemn him, adding more depth to the story.
Well, the other superheroes in their universe could also be supporting characters. Maybe Batman, as Robin's mentor, would play a crucial role. He could be disappointed but also guide Robin on how to handle this revelation. Another possibility is Oracle. She has a lot of knowledge and resources and could help Robin figure out how to deal with the public perception of him as Red X. And then there are other sidekick characters who might relate to Robin's situation and offer their own experiences and support.
The themes might include redemption. If Robin has been involved in some not - so - noble deeds as Red X, the fanfiction could focus on his journey to make amends. There may be a theme of self - discovery as well. Discovering he's Red X might make him question who he really is and what his true motives are. Additionally, friendship is likely a theme. His friends' reactions and whether they can forgive and support him through this revelation.
Villains from the Batman rogues' gallery are likely kidnappers. For instance, the Riddler might kidnap Red Robin to challenge Batman to solve his riddles to get him back. Another one could be the Penguin. He might see Red Robin as a valuable hostage to bargain with for more power or money in Gotham's underworld. Black Mask is also a possibility. He's always looking for ways to gain an edge over the other criminals and having Red Robin as a captive could be part of his scheme.
I think it would be Spider - Man. Since he's also relatively young and has a sense of humor. He would be able to relate to Robin on a more personal level compared to the other Avengers. They could start chatting about their cool gadgets and how to use them in different situations.
For Naruto's side, Sasuke could be a main supporting character. He might be initially skeptical about Naruto's relationship with Rangiku but eventually comes around. Sakura could also be there, helping with the preparations for the wedding. On Rangiku's side, Ichigo could be a key support. Since he has experience with different worlds, he could help bridge the gap between Naruto's world and Rangiku's. Toshiro Hitsugaya, Rangiku's captain, would also be involved, either reluctantly giving his blessing or being a bit overprotective at first.
Obviously, Robin would be one of the main characters. And then, of course, the Avengers members like Iron Man, Captain America, Thor, etc. would be there as well.
Another possible pairing could be Sasuke and Elsa. Sasuke has his own dark past and a brooding personality. Elsa also has her own internal struggles with her powers. They could bond over their shared experiences of having to control something within themselves that others might fear. And their cool and somewhat aloof demeanors could make for an interesting dynamic.
Alec might also play an important role as a supporting character. He could be the voice of reason for Jace, making sure he doesn't make any hasty decisions. And Luke would surely be involved. As someone who has always been like a father figure to Clary, he would offer his wisdom and support, and maybe even help them figure out the financial aspects of having a baby so young.
Sasuke and Magneto. Both are complex characters with a bit of a dark side. They could either become enemies as their goals might clash. Sasuke is on a journey to gain power for revenge, and Magneto wants to protect mutants but sometimes uses extreme methods. Or they could form an unlikely alliance, learning from each other's determination and power - seeking motives.
Anakin Skywalker could be a key supporting character. He was her master, and his influence on her growth as a Jedi was significant. Obi - Wan Kenobi might also be present. His wisdom and different approach to the Force compared to Anakin could offer Ahsoka different perspectives on her own growth. Additionally, Rex, her clone trooper friend, would be likely. Their relationship was strong, and he could be there to support her in various situations.
Other minor characters from the Teen Titans universe might also make an appearance. Maybe some of the villains that are associated with Red X could be there in the background, influencing his actions towards Starfire. Or some of the civilians that the Teen Titans protect, who could be caught in the crossfire of this struggle between Starfire and Red X, and their presence could add more complexity to the story.