One possible storyline could be Maddie dealing with the challenges of her pregnancy while hiding her siren identity from the outside world. She might struggle to keep her powers in check as her hormones change. Another could be that she discovers she's pregnant and has to find the father, who may or may not be aware of her true nature. There could also be a storyline where her pregnancy is a threat to the siren community as it goes against their rules or traditions.
A storyline could involve Maddie's friends and family in the fanfiction. Her friends might be really excited about the pregnancy, but also worried for her safety. They could try to protect her from those who might want to harm her because of her siren status and the unborn child. And her family, if they are part of the siren world too, might have mixed reactions, some supporting her while others thinking she's made a big mistake.
Perhaps in the fanfiction, Maddie's pregnancy could be a sign of something greater in the siren world. It could be prophesied that a child born to a siren under certain circumstances will bring about change. So she has to deal with not only the normal pregnancy stuff but also the weight of this prophecy. She might be hunted by those who want to use the baby for their own gain or those who want to stop the prophecy from coming true.
Well, a storyline might involve Maddie's pregnancy being a turning point in her life. She could start to reevaluate her relationships, both romantic and platonic. For example, if she was in a rocky relationship before, the pregnancy could either make it stronger or break it apart. She may also face challenges in the Nashville music scene because of her pregnancy. Some people might not take her as seriously as a musician anymore, but she could prove them wrong by creating some amazing music inspired by her upcoming motherhood.
Maddie's siren nature might make her pregnancy more difficult. For example, sirens are often associated with water, and her body's need for water could be intensified during pregnancy. She might need to be closer to water sources more often than a normal human pregnant woman.
One possible storyline could be that Zanessa discovers they are pregnant unexpectedly. They then have to deal with the reactions of their friends and family. Some might be overjoyed while others could be concerned about their future. They would need to make decisions about their careers and how to balance impending parenthood with their personal and professional lives.
One possible storyline could be about how the pregnancy affects Celestia's daily duties in her magical realm. She might have to delegate more tasks as she experiences the physical and emotional changes. Another could be the discovery of the pregnancy and how the other characters in the story react, whether it's with joy, concern, or a mix of both.
A story could also focus on the magical or unique aspects of their pregnancy if there are any in the fictional world they belong to. For instance, if there are special powers or abilities that the babies might inherit, they could start to sense those during the pregnancy and it could lead to some interesting adventures as they try to understand what it all means.
One possible storyline could be that Castiel's pregnancy is a result of some magical or otherworldly occurrence. His friends in the story might be in a panic trying to figure out how to help him through the labor. Maybe they have to search for a special midwife or healer who can understand the unique nature of his situation.
A third storyline could be Erin's self - discovery during pregnancy. She might find new strengths within herself as she prepares to become a mother. She could also face insecurities from her own past, like if she had a difficult relationship with her own mother, and be determined to break that cycle for her child.
A storyline could revolve around the pregnancy being a surprise to both of them. They could initially be in denial or scared, but then gradually come to terms with it. Maybe they start making plans for the future, like finding a safe place to live and raising the child away from the chaos of their usual supernatural battles. They might also discover new powers or abilities related to the pregnancy, which could be both a blessing and a curse as they try to figure out how to control them.
One possible storyline could be that they face challenges from their families or the vampire society they belong to. Maybe there are concerns about the half - vampire nature of the baby and how it will be accepted. Another could be that they go on a journey to find a safe place to raise their child away from the chaos and danger that often surrounds them.
One possible storyline could be Robin dealing with the reactions of her friends. For example, Ted might be overly protective, while Barney could be in shock at first but then start making wild plans for the future. Another could be Robin's own internal struggle as she adjusts to the idea of motherhood, given her career - oriented nature. Maybe she worries about how it will affect her job as a news anchor.