Another theme is the exploration of their contrasting personalities. Armin is often seen as the intelligent and more reserved one, while Reiner is the strong - willed and sometimes conflicted. Fanfics play around with how these differences can create an interesting dynamic between them, like in 'The Opposites Attract' fanfic where their differences actually draw them closer.
One popular Armin x Reiner fanfic is 'The Unlikely Bond'. It delves deep into their relationship, exploring how their different personalities complement each other. The story starts with them having to work together on a mission and gradually realizing their mutual respect and growing feelings.
Reiner did die in the manga. His death was a result of a series of events and conflicts that had been building up throughout the storyline. It had a major impact on the plot and the other characters.
In many 'Batman Beyond' fanfictions where Dana finds out, it could be about her finding out Bruce Wayne is Batman. Maybe she stumbles upon some evidence in the Batcave or notices some similarities in Terry's behavior to Bruce. For example, she might notice Terry's fighting style is similar to what she's heard about Batman's. It could also be that she discovers some secret technology related to Batman that leads her to the truth.
Ginny's reaction could also involve a sense of helplessness at first. But then she'd quickly gather herself and use her resources. For instance, she might call on her friends and family for help. She'd be by Harry's side constantly, using her presence to comfort him and also using her knowledge of magic to try and ease his pain.
For Merlin, there are both good and bad consequences. On the bad side, some of the more traditional and anti - magic people in Camelot might try to oppose him. However, since Arthur now knows, he has a powerful ally. Arthur can protect Merlin from those who would do him harm. Also, Merlin can now be more open about using his magic for the good of Camelot, which is a positive change.