There could be a young unicorn named Starlight. He might be a brilliant but overconfident student who Twilight has to guide. Another character could be a pegasus named Rainbow, who is always getting into trouble and Twilight has to keep in line.
Well, it could be that the fanfic is set in an alternate universe where Twilight, instead of being a princess, is a headmaster. The story could revolve around the relationships she forms with the students. For example, she might take a special interest in a misfit student and help them find their place in the school. There could also be a sub - plot about a rival school trying to undermine Twilight's school, and she has to use her wisdom and magic to protect it.
One of the main characters could be Twilight Velvet's mate. He would play an important role in the story, perhaps being there for her during the pregnancy and helping with the care of the foal. Another character could be Twilight Velvet's mother. She might offer her own experiences and wisdom about raising a foal.
Her friends like Pinkie Pie, Rainbow Dash, Applejack, Rarity and Fluttershy are likely to be main characters. Pinkie Pie might bring her usual cheer and parties to celebrate Twilight's new form. Rainbow Dash could be both impressed and a bit competitive, trying to keep up with Twilight's new abilities in her own way. Applejack would offer her down - to - earth advice and support. Rarity might be excited to create new outfits for Twilight as an alicorn. And Fluttershy would be there with her gentle nature, providing a calming presence.
There could be students. Students often play important roles in a school - based visual novel. They might be the ones causing trouble that the headmaster has to deal with, or they could be the ones with great potential that the headmaster wants to nurture.
Fluttershy might be a key character. Her gentle and kind personality could have a big influence on Twilight's daughter. The daughter could learn about compassion and caring for animals from Fluttershy. And of course, Rarity could be in it too. Rarity could help the daughter with her appearance and self - confidence, perhaps creating some beautiful outfits for her.
I'm not entirely sure as it's a fanfic, but it could include the main characters from the Twilight series like Bella and Edward. They might be involved in the events around the twilight lagoon, perhaps exploring it or having some kind of encounter there.
Obviously, Bella and Edward would be great main characters for a reunion fanfic. Their relationship was central to the original series, and a reunion could show how their love has evolved over time. They could be dealing with new challenges as a couple, like raising their daughter Renesmee in a world that still has some threats.
Maybe it's a side character from the original Twilight books that the writer decides to give more depth to. Like one of the lesser - known vampires in the Volturi coven who has a secret past and motives that are explored in the fanfic.
Edward is often involved. Since he's so close to Twilight, he would be there to support her or sometimes be a source of conflict as he tries to help in his own way but might not always understand what she's going through. Bella's family, like Charlie, could also be main characters. Charlie might notice the changes in Twilight and try to figure out what's wrong. And then, her vampire friends like Alice could play a significant role. Alice might use her ability to foresee things related to Twilight's PTSD, either to help or sometimes make things more complicated.
Edward would definitely be one of the main characters. His relationship with Bella, now a geisha, would be very interesting to explore. He might be both intrigued and a bit confused by this new side of her.