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.
The Last Song is a work of fiction. Usually, it involves elements of creativity and imagination to craft a story that doesn't directly correspond to real-life events or people.
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.
The theme of The Last Song often centers around family, love, and personal growth. It explores the complex relationships and the journey of self-discovery for the main characters.
The Last Song is actually a work of fiction. It was crafted by the imagination of the writers and not based on real events or people. The plot and characters are made up to engage and move the audience.
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.