Obviously Clary herself is the central character. Jace is also very often involved as he is Clary's love interest. Alec and Isabelle Lightwood might also play important roles. They could be the ones helping Clary through her pregnancy, giving her advice or protecting her from any threats.
Clary is at the heart of it. Jace is crucial as the potential father. But don't forget Luke. As Clary's step - father, he could be a source of great support. He might be the one who tries to keep the peace between Clary and the Clave if they find out about her pregnancy. Also, Maia could be involved, offering her own brand of support as a werewolf friend of Clary's.
Definitely Clary and Jace are the main ones. Magnus Bane could also be involved. He might use his magic to help Clary during her pregnancy, like ensuring a healthy pregnancy or protecting her from any dark magic that could harm the baby. Simon Lewis could also be there, providing a different perspective as Clary's human friend.
One popular storyline could be how they deal with the challenges of being young and expecting in the dangerous world of Shadowhunters. They might have to face threats from demons while also preparing for the baby.
Mal herself is likely to be a very popular character in such fanfiction, as she is a central figure in the 'Descendants' world. Her story arc can be easily adapted to include a pregnancy plot. Evie might also be involved, either as a friend supporting Mal or having her own related story. Jay could be another character who might play a role, perhaps as a protector or someone with a connection to the events related to the pregnancy.
Loki is the main one for sure. His wife, of course. And then there could be other Asgardian characters like Heimdall. Heimdall, with his all - seeing abilities, could play a role in protecting Loki's wife during her pregnancy. There might also be some of Loki's old allies or foes from his past adventures who get involved in the story, either to help or cause trouble.
Jaune could be a popular character in such fanfictions. If Ruby is in a relationship with him, he would play a major role in the story. He could be shown as being nervous yet excited about becoming a father. Pyrrha might also be involved in some way, perhaps in flashbacks or as a guiding spirit for Jaune, even though she's no longer alive in the main series.
Alec would likely become more protective. His natural instinct to safeguard would intensify not just for Clary but also for their unborn child. He'd be constantly on guard against any potential threats.
Rias Gremory is often a popular character in such fanfics. Given her central role in the original Highschool DxD series, her relationship with Issei could be explored in the context of a pregnancy. Her status as a devil and the leader of her peerage would add a lot of complexity to the story if she were to become pregnant.
Well, in some fanfictions, the story could focus on the father's role. If it's Jace, for example, he might be overprotective. There could also be a plot where Clary discovers new powers or abilities that are related to her pregnancy, like some kind of enhanced intuition for protecting the unborn child.
Well, obviously Gaster is the central character as it's about his pregnancy. But often, other characters from the same fictional world might be involved. For instance, characters who are friends or colleagues of Gaster could be there to support or oppose the situation. It might also include characters who have some sort of special connection to Gaster's unborn child, like a potential mentor or an enemy who wants to harm the baby.
Well, their relationship in the original series has a lot of potential for exploration in fanfiction. They start off as somewhat at odds with each other, but as they face common enemies and challenges, there is room for their relationship to grow and change in many different ways that fanfiction writers like to explore.
Kristoff is often involved. He would be there to support Anna, and might be a bit nervous about becoming a father. Olaf could also be a popular character in such fanfictions. He'd be his usual cheery self, trying to make the pregnant Anna and Elsa happy with his funny remarks.