A cool plot idea could be that the child has a unique power that neither Robin nor Raven have. This power could attract the attention of an ancient evil force that was once sealed away. So, Robin and Raven have to team up with their friends to not only protect their child but also the whole world from this new threat.
The story could start with the discovery of Raven's pregnancy. Robin is overjoyed but also worried about how their lives will change. As Raven's pregnancy progresses, they start preparing for the baby. But there are also signs that something is wrong, like strange dreams Raven has. It turns out there is a prophecy about their child that they need to figure out and deal with.
Perhaps the fanfic could revolve around the child being sent to the future accidentally. Robin and Raven then have to travel through time to get their child back. Along the way, they see how their actions in the present will affect the future, and they also learn more about their relationship and their roles as parents.
Well, a plot could involve a mystery in the high school that only Raven and Robin seem to be aware of. They team up to solve it, and during their investigations, they discover secrets about each other that bring them closer. Maybe Raven has some hidden powers that she's been afraid to show, and Robin's detective skills help her come to terms with it. And in the process, a romantic relationship starts to bloom.
A cool plot could be that there's a mysterious threat targeting all of Batman's allies. Robin and Batgirl team up to not only find out who's behind it but also to protect each other. Along the way, they share some personal stories from their pasts that bring them closer together.
Some fanfics might explore an alternate universe where their roles are different. For instance, Robin could be a powerful mage like Tharja, and they bond over their shared magical abilities. Or perhaps they are from different kingdoms originally and their relationship has to navigate the politics between the two kingdoms while also dealing with their growing feelings for each other. This can lead to a lot of complex and interesting storylines.
One idea could be a story where Robin, Starfire and Raven have to team up against a powerful new villain that is immune to their individual powers. They must learn to combine their abilities in a new way. For example, Robin uses his strategic mind to find the villain's weakness, Starfire provides the brute force, and Raven uses her magic for defense and to disrupt the villain's power source.
One plot idea could be that Raven and Beastboy are paired for a school project. As they work together, they start to understand each other on a deeper level. Raven discovers Beastboy's insecurities beneath his fun - loving exterior, and Beastboy realizes Raven's not as cold as she seems. This new understanding could lead to a budding friendship that might turn into something more.
One idea could be that Christopher Robin gets lost in the Hundred Acre Wood as an adult and Pooh has to help him remember all the wonderful things from his childhood. They could go on a journey to find the special places that they used to visit together, like the bridge over the stream or the bee tree.
Maybe the OC is from a long - lost island with unique knowledge. Robin is interested in the historical aspects of this knowledge and Nami sees the potential for great treasures. The OC then has to deal with the different personalities of Robin and Nami. Robin is calm and intellectual, while Nami can be feisty. Their interactions lead to a series of adventures and a deepening of their relationships.
One great 'raven x robin fanfic' could be 'Shadows of Unity'. It beautifully explores their complex relationship, with the author delving deep into their personalities. Another one is 'Midnight Bonds' which has an interesting plot where they team up against a common enemy and in the process, their relationship evolves. There's also 'Eclipse of Hearts' which focuses on their emotional connection in a more angsty way.
The OC could be a lost traveler who stumbles upon Raven's hideout. Raven at first is cautious but then decides to help the OC find their way back home. Along the way, they encounter various obstacles like a group of bandits or a magical storm. As they face these challenges, they develop a bond. Another plot is that the OC is a healer who comes to a place full of injured people. Raven is one of the wounded and the OC's gentle and kind nature makes Raven open up in a way she hasn't before. However, there is a group that wants to stop the OC from healing people for their own evil purposes, so Raven and the OC have to fight back.
One idea could be that Robin gets trapped in an alternate dimension where the villains are in control and Batman has to figure out a way to bring him back. Another could be a story where Batman is injured and Robin has to take on a major villain alone, learning to trust his own instincts more. Maybe a plot where they encounter a new, powerful ally who turns out to have a hidden agenda that threatens Gotham.