Domon Kasshu could be the one to save the fan. He's the main character in G Gundam, and he's always ready to fight for justice. He would surely not stand by while a fan of his universe is kidnapped.
Maybe the other Gundam pilots from different countries in the G Gundam series could team up to rescue the fan. Each pilot has their own unique skills and abilities, and together they could form a powerful force to take on Rain and free the fan.
Perhaps in this fanfiction, Rain is from an opposing force to the G Gundam universe. She kidnaps the G Gundam fan as a way to gain information about the Gundams. The fan might be a super - knowledgeable person about G Gundam, and Rain wants to use that knowledge for her own purposes, like to develop a counter - measure against the Gundams.
There is a fanfiction called 'Beyond the Gundam Tournament'. It takes place after the events of the G Gundam series. It explores what the characters do next and how they adapt to a world without the tournament. It has a lot of character development and some great emotional moments.
Piccolo might also be a savior. He has a soft spot for Gohan since they trained together. He could use his strategic mind and powerful attacks to outwit Raditz and rescue Gohan. Maybe he teams up with Goku for an even more epic rescue mission.
The plot could involve the Dark Gundam capturing Rain as a way to lure in other characters. Since Rain is likely to have friends or allies, the Dark Gundam could be using him as bait. This would then lead to a rescue mission by those who care about Rain, with lots of action and drama as they try to outwit the Dark Gundam.
The rain could be related to the Dark Gundam itself. Maybe the presence of the Dark Gundam somehow affects the weather, and the rain is a result of its dark power. This could create an interesting plot point where characters have to deal with not only the Gundam but also the environmental changes it brings, like the constant rain.
Her friends, like Damon and Stefan, might come to her rescue. They are often the ones to jump into action when one of their own is in danger.
Another idea is a crossover where the technology of G Gundam is introduced into the Naruto world. Maybe the Hidden Villages start to develop Gundam - like mechas using their own unique ninja techniques. This would completely change the dynamics of battles in the Naruto universe.
Rain is the key character here. He's the one in the difficult situation of being shackled to the Dark Gundam. The Dark Gundam is not just a machine but can be considered a character with its own motives and powers. Additionally, there could be a mentor - like figure for Rain. Maybe an older, more experienced pilot who has some knowledge about the Dark Gundam and tries to guide Rain in his struggle. There could also be antagonists other than the Dark Gundam, such as those who oppose Rain's attempts to free himself for their own self - serving reasons.
The fan could be a young journalist who was trying to get an exclusive interview with Harley Quinn. Harley, not trusting the media, kidnaps the journalist thinking they will expose her secrets.
Batman could be a likely candidate to save Wonder Woman. He has a long history of dealing with the Joker and his antics. His detective skills would help him track down where the Joker is keeping Wonder Woman.