In a Flash - pretends - to - be - Spider - Man fanfic, perhaps Flash pretends to be a fan to get closer to Peter Parker. He thinks that by faking his love for Spider - Man, he can find out Peter's secret identity. So he starts hanging around Peter all the time, acting like a superfan. But Peter sees through his act and decides to play along and teach Flash a lesson about being a true friend and not using people for personal gain.
Well, the plot could be that Flash, who is usually a bit of a bully, suddenly decides to pretend to be a huge Spider - Man fan. Maybe he does it to impress a girl who loves Spider - Man. He starts dressing up like Spider - Man in a really comical way, with a homemade suit that's all wrong. He might try to do Spider - Man - like stunts but fails miserably every time, creating a lot of chaos and humor in the story.
The story could be about Flash trying to write a Spider - Man fanfic of his own where he inserts himself as the main character who is a super - fan of Spider - Man. He writes all these wild adventures where he meets Spider - Man and they become best friends. But in reality, his real - life actions don't match his fanfic self. His friends start to notice this disconnect and it leads to a series of events where Flash has to face the truth about himself and his false pretenses.
The other characters' reactions could be quite diverse. Flash's friends might be supportive at first, thinking it's just a new hobby of his. But as his pretense continues, they might start to get annoyed. The bullies in Flash's clique could see it as a weakness and start to pick on him. Meanwhile, the people who are actually Spider - Man fans might be outraged that Flash is faking it just for attention. They could confront him and expose his falsehood, leading to a big drama in the story.
Well, in a Spider - Man Flash crossover fanfiction, there could be an epic race between the two. The Flash could be testing his speed against Spider - Man's agility and web - slinging skills. Maybe they start as rivals but end up teaming up to face a common enemy like a super - fast villain that only their combined powers can defeat.
Perhaps in the fanfic, Ant Man accidentally shrinks himself too much and gets lost in Spider Man's suit. Spider Man then has to figure out how to get him out without harming him. Meanwhile, they discover that there's a mini - world inside the suit with its own set of problems, like tiny villains causing chaos, and they have to deal with that together.
Another possibility is that some sort of cosmic event makes them both super - charged, Naruto becoming godlike and Spider - Man reaching an ultimate form. They are then chosen to stop an interdimensional threat that could destroy both their worlds. They would have to learn to trust each other quickly and use their combined powers to save the day.
The plot could involve a new villain who targets both of them because of their relationship. This villain might be someone who wants to disrupt the harmony between Earth and the cosmos. Spider - Man and Captain Marvel have to work together to defeat this enemy while also dealing with the challenges of their new - found married life.
Maybe in the fanfic, Spider - Man and Wasp are framed for a crime they didn't commit. They then have to prove their innocence while also dealing with other superheroes who are after them. They would need to combine their skills, with Spider - Man using his strength to fight off attackers and Wasp using her stingers to defend themselves when in close combat.
There could be a new villain emerging in Spider Man 4 story. Maybe it's someone from Peter Parker's past, like an old classmate who got exposed to some strange experiment and turned into a super - powered foe. Spider - Man would then have to figure out how to defeat this new threat while also dealing with his normal life issues, like his job at the Daily Bugle and his relationships.
It could involve Spider-Man fighting off a powerful villain to save the city. Maybe a new threat emerges that challenges his powers and his determination to protect the people.
In a fanfic, Spider - Man could be injured while on a mission with the Avengers in outer space. Maybe they are exploring an alien planet and are attacked by some sort of bio - mechanical creatures. Spider - Man is separated from the group and gets severely injured by one of the creatures' acidic attacks. His injury makes it difficult for him to use his powers effectively, and the Avengers have to find a way to both get him back to Earth and find a cure for his injury.
One possible plot could be that the Titans somehow cross into Spider - Man's universe. Spider - Man initially mistakes them for some new kind of giant robots or mutants. He tries to fight them using his web - slinging and acrobatic skills. But he quickly realizes they are much more difficult to defeat as they keep regenerating. Meanwhile, some of the Survey Corps members from Attack on Titan also cross over. They team up with Spider - Man, teaching him about the Titans' weak points at the back of their necks. Together, they fight to keep both universes safe from the Titans.