In the Vampire Academy setting, Rose's pregnancy could be a huge shock to the system. The strict rules and hierarchies of the academy might not be prepared for such a situation. Her pregnancy could lead to new alliances being formed, like other dhampirs or vampires coming to her aid. Also, the medical facilities at the academy could play a role in her prenatal care, and there could be a whole sub - plot about the secrecy or lack thereof regarding her pregnancy within the academy walls.
Dimitri is an obvious choice. Their relationship in the original series is so complex and full of passion. In fanfiction, it can be explored even further, like what would happen if they had to face an even greater threat together. Adrian also makes for an interesting pairing. His charm and different approach to life compared to Rose can create a lot of interesting storylines.
A great fanfiction idea could be Rose getting transported to a different time or dimension. In this new place, she has to adapt quickly and find a way back home. Along the way, she meets different versions of the characters she knows and forms new alliances. This type of story could really test her character and show how resourceful she is.
The various villains in the show could also play a role. They might see Enid's pregnancy as a weakness and try to target her. But this could also be a chance for Enid to prove that being pregnant doesn't make her any less of a hero. She could use her wits and the support of her friends to outsmart the villains.
One idea could be that Rose's pregnancy brings new challenges to her training at the Vampire Academy. Maybe she has to deal with physical limitations while still trying to prove herself. Another could be that her pregnancy causes a stir among the different vampire factions, some seeing it as a sign of hope and others as a threat.
One possible storyline could be that Rose has to deal with the reactions of her friends and family. Lissa might be initially shocked but then become very supportive. Dimitri, if he's still in the picture, could be overprotective. Another aspect could be how Rose manages her training while pregnant. Maybe she has to find new ways to stay in shape and keep her skills sharp for when the baby arrives.
A fanfiction could involve Rose being captured by Strigoi. She then has to use her wits and combat skills to escape. Along the way, she discovers some secrets about the Strigoi that could change the way the dhampirs and Moroi view them. For example, she might find out that some Strigoi were forced into their state against their will in some strange, dark ritual.
One common character paired with Rose could be Dimitri. Even in the human world fanfictions, their relationship is often explored. He might follow her to the human world to protect her or they could be reunited there after being separated in the vampire world. Their dynamic of mentor - protege and their underlying romantic tension would still be a major part of the story.
Dimitri would be devastated. He might isolate himself from others and blame himself for not being able to protect her. Lissa would be heartbroken. She would feel like she lost a part of herself. Christian might become more protective of Lissa, seeing how fragile she is after losing Rose. The other dhampirs would be in shock. Some might look for someone to blame, while others would try to find a way to honor Rose's memory.
I really liked 'Lissa and Rose: The Unseen Adventures'. This fanfic takes the two on a journey outside of the normal Vampire Academy setting. They face new challenges together, which makes their friendship even stronger. The writing is quite engaging and it's easy to get lost in the story.
Love is a very common theme. Many fanfictions focus on the romantic relationships between the characters, like Rose and Dimitri. Their love story is often explored in different ways, sometimes with added drama or new challenges.