Well, Izuku is the central figure here as he takes the initiative to call out Aizawa. Izuku is known for his sense of justice and determination. Aizawa, a respected teacher in the original series, becomes the focus of Izuku's call - out in this fanfiction. There might also be other minor characters from the original 'My Hero Academia' universe who could be involved in the background, perhaps classmates of Izuku who are affected by the situation in the fanfiction.
The main characters are Izuku Midoriya, the protagonist of the original story, and Shota Aizawa, his teacher. In this fanfiction, Izuku's role is to point out something wrong about Aizawa as portrayed in the fan - made story. Aizawa, on the other hand, is the target of Izuku's call - out, whether it's about his actions, attitude, or some other aspect as written in the fanfiction.
Obviously, Izuku and Aizawa are the main characters. Izuku is the one who is doing the calling out, and Aizawa is the one being called out.
Well, it could be about Izuku confronting Aizawa over some misrepresentation in the fanfiction. Maybe Izuku doesn't like how Aizawa is being portrayed as too strict or unfair in the fic.
It could be Aizawa himself if he's being controlled by something or has some sort of ulterior motive that is not in Izuku's best interest. But if not Aizawa, then there could be a hidden villain who is manipulating Aizawa to kidnap Izuku.
In some fanfictions, Aizawa might be under the influence of a villain's quirk that makes him act against his will. So, he kidnaps Izuku, but later on, he realizes what he's done and tries to make amends. This could lead to a story full of drama and redemption.
Perhaps Izuku was skipping class and went to the roof. Aizawa noticed his absence and suspected he might be there.
Aizawa may also interact with Izuku's family during family events or gatherings in the fanfic. He could be a guest and during that time, he could share his insights on Izuku's growth and development. This would not only strengthen his relationship with Izuku but also with his family as a whole.
Aizawa is known for his strict and somewhat reserved nature. This would have a significant impact on Izuku. Izuku, who is often eager and a bit impulsive, would learn to be more patient under Aizawa's guidance. Aizawa's ability to see the potential in his students despite their flaws would also make Izuku more confident in his own abilities. He would know that his father figure believes in him, and that would encourage him to keep pushing himself. Moreover, Aizawa's dry sense of humor might also influence Izuku's own sense of humor, making him a bit more sarcastic in a light - hearted way.
There could be his friends like Ochaco Uraraka. She might be in a position where she's trying to understand Izuku's situation and help him. Maybe she tries to convince the people forcing Izuku to give him some space.
One scenario could be that Izuku is on the roof to get some fresh air and clear his head. Aizawa, being the observant teacher he is, follows him there. He could then share some of his own experiences with Izuku, like how he overcame difficulties in his youth, which would inspire Izuku and strengthen their relationship in the fanfiction world.
Some dedicated My Hero Academia fanfiction forums might also have these stories. You can join these forums and ask around. Members are usually helpful in pointing you to the right stories.
One good one might be 'Aizawa's Guidance for Izuku' which focuses on their unique mentor - mentee relationship evolving in an interesting way. It has great character development.