One aspect to consider in this fanfiction could be the extreme devotion Mikasa has in a yandere state. Yandere characters are known for their obsessive love, and Mikasa's love for Eren was already intense in the original series. In the fanfiction, this might be amplified, leading to situations where she becomes overprotective and possessive of Eren, perhaps even to the point of excluding others from his life. This could create a lot of drama and conflict, especially when Eren's own goals and relationships with other characters are taken into account.
Obsession is a common theme. Yandere Mikasa is obsessed with Eren, which drives her actions. Another theme could be protection. Since Mikasa has always been protective of Eren, in a yandere context, it becomes an over - the - top form of protection where she might eliminate any perceived threats to him.
One common theme is possessiveness. Since Mikasa is yandere, she is extremely possessive of Eren. Another theme is protection. Mikasa feels the need to protect Eren at all costs, which can sometimes border on the obsessive. And the theme of love - her love for Eren is so intense that it drives her yandere behavior.
One popular 'Attack on Titan' fanfic with a Yandere Mikasa and Eren theme is 'Bound by Obsession'. It delves deep into Mikasa's over - protective and possessive nature towards Eren. Another is 'Mikasa's Dark Devotion' which shows how her yandere tendencies play out in different scenarios within the Attack on Titan universe.
In yandere x reader fanfics, yanderes usually display intense emotions. Their love for the reader is not the normal kind; it's more of an obsessive love. They may have a dual personality where they can be extremely sweet and loving one moment, but if they feel threatened in their relationship with the reader, they can turn very dangerous and menacing.
Female Eren in this fanfiction is often portrayed as headstrong. Just like her male counterpart, she has a strong sense of justice and is determined to fight for what she believes in. She is also likely to be brave, not afraid to face danger head - on, whether it's in battle or when confronting the complex relationship with Levi.
One idea could be a story where Levi and Eren are on a dangerous mission together. They start off not getting along well due to their different personalities. Levi is strict and methodical while Eren is impulsive. But as the mission progresses, they gradually learn to understand and rely on each other. For example, Eren might save Levi from a Titan in a moment of quick thinking, and Levi in turn teaches Eren some crucial combat skills.
In a yandere phobos x will fanfic, one aspect to consider is the power dynamic. If Phobos has more power, it can intensify his yandere tendencies. For example, he could use his influence to isolate Will. The fic might also focus on Will's reaction to Phobos' yandere behavior. Will could either be scared or, in an interesting twist, gradually come to understand and even accept Phobos in some way.
Look for fanfic communities dedicated to the source material that Phobos and Will are from. There, you can ask for recommendations of 'yandere phobos x will fanfic'. Members are usually quite helpful in sharing their favorite stories in this genre.
One aspect of Levi x Eren family fanfiction could be the exploration of their relationship in a family - like dynamic. It might involve how they support and protect each other within this new family structure. For example, Levi could be a strict but caring figure, while Eren is the one with new - found responsibilities in this family.