There may be. There are fanfic communities that strive to create content suitable for a wide range of audiences. In the case of an 'eren gets mikasa pregnant fanfic', it could be written with themes like family values, the growth of their relationship, and the anticipation of new life. For example, it could detail how Mikasa's character might change as she prepares to be a mother, and how Eren steps up to support her, all while keeping the story appropriate for all ages.
One of the main themes would be the sense of loss and fear. The kidnapped boy Eren's family would be experiencing a great deal of fear for his safety and a sense of loss as he is taken away. Another theme could be the search for justice. As the story progresses, the search for Eren would likely involve the pursuit of the kidnapper to bring them to justice.
One such book could be 'The Disappearance of Eren'. It follows the harrowing journey of a boy named Eren who gets kidnapped. The story is filled with mystery and suspense as the characters around Eren try to find him. It delves into the psychological aspects of the kidnapper and the impact on Eren's family.
One common plot twist is that the kidnappers turn out to be people Eren thought he could trust. For example, in some fanfics, it could be someone from his own military unit who has a hidden agenda. This adds a layer of betrayal and makes the story more complex.
There's a fanfic titled 'Kidnapped Eren: A Different Path'. Here, Eren is kidnapped by a rogue group within the walls. They have different motives than the usual antagonists. It delves into the politics and power struggles within the world of Attack on Titan, while also showing Eren's struggle to escape and his growth during the ordeal. It's quite an interesting take on the concept.
In many fanfictions where Gil gets kidnapped, it could be for various reasons. Maybe it's by a rival group who wants to use him as a bargaining chip against his friends. For example, in some stories, Uma's crew might be targeted because they are seen as a threat in the Isle of the Lost. Gil, being a part of that crew, gets kidnapped. Writers often use this plot device to create drama and show the loyalty and courage of the other characters as they try to rescue him.
The main characters are obviously Eren and Mikasa. Eren is often portrayed as a complex character with strong will and determination. In this fanfiction context, he will be dealing with the new situation of becoming a father - to - be. Mikasa, on the other hand, is a strong - willed and loyal character. Her pregnancy will likely bring out different aspects of her personality, such as her nurturing side.
It could be a new character created specifically for the fanfiction. Maybe a young scientist who is working on a project related to the super - soldier serum. Since Bucky has a history with the serum, this would create an interesting dynamic.
One idea could be that Sam is kidnapped by a group of rogue hunters who think he's gone too far in his use of demon powers. They lock him in an abandoned bunker and try to 'exorcise' the 'demon' out of him, not realizing he's in control. His brother Dean has to race against time to find him, following a series of cryptic clues left by the kidnappers.
Natsu was walking through the forest one day when suddenly a group of dark mages emerged from the shadows. They quickly overpowered him with some sort of magic -binding spell. They dragged him away to an old, creepy lair. His friends back at the guild soon realized he was missing and set out on a search mission. Happy flew around frantically looking for any sign of his friend. Lucy, Gray and Erza teamed up and followed some leads they found in the forest. They were determined to rescue Natsu no matter what it took.