There could be a plot twist where Damian discovers that he has some sort of genetic connection to the baby that he didn't expect. Maybe there's a long - lost family power or curse that could affect the unborn child. This would force him to confront his own family history and figure out how to protect Raven and the baby from any potential harm.
A plot twist could be that the pregnancy is not what it seems. Maybe it's an illusion created by a villain to distract them from a bigger threat. Raven and Damian might initially believe it's real and start making all these plans, only to find out later that they've been tricked.
One possible plot idea could be the two of them dealing with the initial shock of the pregnancy. They might struggle with how to tell their families and friends. Another could be them preparing for the baby, like setting up a nursery in the Batcave or Raven's mystical realm. They could also face challenges from villains who see the unborn child as a potential threat or a tool for their evil plans.
One possible plot twist could be that the pregnancy is a result of some sort of magical or alien interference. Maybe there was a spell gone wrong or an experiment that affected them in unexpected ways. This would add an element of mystery and danger to the story as they try to figure out what exactly happened and how to deal with it.
There are several out there. Some focus on the medical side of Raven's pregnancy in a world where they have access to both normal and supernatural medical help. In one fanfiction, Damian is overly protective, which causes some tension between them as Raven still wants to be independent. It's a great exploration of their characters. Another fanfic shows how their families react to the pregnancy. Damian's family has their own set of expectations, while Raven's side has different concerns. These elements make for an engaging read.
Another possibility is a fanfiction set in an alternate universe where Raven and Damian are already married and they've been trying to have a baby for a while. When Raven finally gets pregnant, it's a time of great joy. They could go through all the typical pregnancy experiences like shopping for baby clothes, choosing a name, and decorating the nursery.
One possible plot could be that Damian and Mar face a lot of challenges upon finding out about the pregnancy. Maybe they're young and not fully prepared, so they have to deal with the reactions of their families and friends. Their relationship might be tested as they struggle to adapt to the idea of becoming parents.
Well, it could be a story about how Clarke and Raven's relationship has developed in an unexpected way. Maybe there was some sort of experiment gone wrong that led to Clarke's pregnancy. Or perhaps it's a more emotional plot where their friendship turns into something more complex due to the pregnancy situation.
The plot could involve Raven and Slade being forced into an uneasy alliance due to the pregnancy. Maybe there's a prophecy that their child will have great power, and different factions either want to protect or destroy the unborn baby. Raven struggles with her emotions, as she's not sure if she can trust Slade completely, but she knows she needs his help to keep the baby safe.
You can try Archive of Our Own (AO3). It has a large collection of fanfiction, and you're likely to find many Damian and Raven pregnant fanfics there. Just use the search function and type in relevant keywords like 'Damian and Raven pregnant'.
One possible plot twist could be that their kiss is part of a spell gone wrong. Maybe they were trying to combine their powers to defeat a powerful enemy, and the magic misfired, resulting in an unexpected kiss. This could lead to a series of comical and confusing events as they try to figure out how to reverse the spell without losing their newfound closeness.
Well, perhaps the plot twist is that Gwendolyn is pregnant, but it's not a normal pregnancy. It could be a result of some sort of magical or scientific experiment gone wrong. For example, she was part of a study to find a cure for infertility, and instead, she ended up with an unexpected pregnancy that has strange side - effects. This would change the direction of the fanfiction completely.