It's fairly common. Fans often look for more content related to their favorite shows. Since 'Attack on Titan' has a large and passionate fan base, there are a lot of fanfics available. 'Aot' fans might watch (read) these fanfics to explore different scenarios that the official story didn't cover. For example, they might want to see how a certain character would react in a different situation or what would happen if a major plot event had a different outcome.
There could be a fanfiction where Jean and Mikasa's baby has some special abilities. This causes both excitement and worry among them. They have to figure out how to help the baby control these abilities and keep it a secret from those who might want to use the baby for their own purposes.
There could be various fanfictions. Maybe some that focus on alternative endings, like ones where certain characters survive who didn't in the original. For example, a fanfiction where Erwin survives and leads the Scouts in a different way.
It could mean that a person who is a fan of 'Attack on Titan' (AOT) is reading or watching fan - created fictional works related to AOT. Maybe they are interested in seeing different interpretations or storylines that fans have come up with.
One way is to check on popular fanfiction websites. Look for ones with high ratings and a lot of reviews. For example, Archive of Our Own (AO3) has a large collection of AOT fanfictions. You can search for the most popular ones there.
You should start with creating a setting for your fanfiction. Since they are from a particular world, you can either keep it in that world or create a new one for them. For the story development, think about how the baby changes their relationship. Maybe they become more protective of each other because of the baby. Write in a way that shows the emotions of the characters clearly.
Definitely not. AOT is a work of fiction that combines elements of fantasy, action, and drama. It's set in a made-up world with its own unique plot and characters.