A 'glitchtrap x vanny fanfic' often explores a very dark and complex relationship within the FNAF universe. Glitchtrap is a rather menacing and manipulative character, and Vanny is his sort of 'accomplice'. In these fanfics, their interactions can range from him subtly influencing her actions to full - on domination of her will. It's a very interesting exploration of the power dynamics and the darker side of the FNAF lore.
In this type of fanfic, the characters Vanny and Glitchtrap are central. The fanfic could be about their alliance, perhaps in causing chaos within the Freddy Fazbear's establishment. Vanny, being a follower of Glitchtrap, might be depicted as carrying out his devious plans, which could make for an interesting read as it delves into the psychological aspects of their relationship.
The power imbalance. Glitchtrap has this sort of otherworldly and menacing power, while Vanny is more of a human (or at least a physical being in the game world). The contrast between their 'strengths' makes their relationship in the fanfic really captivating. It's like seeing how a small, perhaps vulnerable character gets caught up in the web of a much more powerful and devious entity.
One interesting plot could be Glitchtrap slowly influencing Vanny's actions in the virtual world and how she then starts to carry out his sinister plans in the real world. For example, he might manipulate her into setting up traps for the other characters in the game's setting.
Many fanfictions depict it as a somewhat symbiotic relationship. Vanny gets power and a sense of purpose from Glitchtrap, while Glitchtrap uses Vanny to achieve his goals in the game world. They depend on each other in a twisted way.
The main differences are in their expressions and some minor details of personality. In the manga, Deku might seem a bit more intense, while in the anime, he's sometimes presented a bit softer.
Deku might be completely shocked at first. Since Bakugou has always been so aggressive towards him, he would never expect such a confession. He might just stand there, mouth agape, not knowing what to say.
His friends could come to the rescue. Bakugo, for instance, might use his explosive power to break into Toga's hideout. He's always been competitive with Deku, but he also cares about him deeply.
In 'deku meets future deku fanfiction', perhaps the future Deku warns the present one about upcoming threats. He could tell him about villains he'll face in the future and how to defeat them. This would give the present Deku an edge in his battles and also in his growth as a hero.