His reaction could be one of confusion. Fanfiction isn't really part of the pure - blood wizarding world he's used to. So seeing Harry doing something so different like cutting fanfiction would leave him scratching his head, not really understanding what Harry is up to or why he's doing it.
Draco could also be intrigued. Despite their differences, he might be secretly interested in what Harry is doing. Maybe he'll ask some questions about the fanfiction, like what it's about or why Harry is cutting it, while trying to maintain his cool and aloof exterior.
In a scenario where Draco finds Harry cutting fanfiction, it could potentially change the dynamic between them. Fanfiction often involves a lot of creativity and personal investment from the writer or editor (in this case, Harry). Draco might not understand this at first. But if he takes a moment to think about it, he could realize that Harry has a passion for this fictional world in a different way. It could be a moment of growth for Draco, where he starts to see Harry not just as an enemy but as a person with diverse interests. Or, it could go the other way and just be another source of conflict between them, with Draco making fun of Harry's hobby and Harry getting defensive.
Charlie may initially be confused. Fanfiction isn't something he might be very familiar with. But once he understands what it is about Harry and Ginny, he might just shrug it off. He's got his own life with dragons and such, so he might not really care all that much as long as it doesn't cause any real - world problems for his sister and Harry. However, if it spreads some false or unflattering rumors in the wizarding community, he might get a bit annoyed.
Snape's view of Harry would likely become more complex. He might see Harry as more vulnerable than he previously thought. His initial disdain might turn into a sort of begrudging concern. He would realize that Harry is dealing with deeper issues than just being the 'Boy Who Lived'.
Deadpool could also be protective. If Spider - Man is a teen, he might see himself as a sort of protector. He could say something like 'Hey, little spider, I got your back since you're just a youngster in this crazy hero business.' He'd probably crack some jokes about it too, like 'You're so young, your suit is probably still in training wheels!'
He might be quite shocked at first. After all, Wolfstar involves his dad's best friend Sirius and his other dad figure Lupin. It's a rather strange concept for him to think about them in a romantic way as he knew them in a different context.
Cedric would be deeply troubled. In the wizarding world, they have their own code of honor and respect. Finding out about Harry's abused fanfiction would go against everything Cedric stands for. He might start to question the morality of the Muggle world that allows such things to be written. He would also feel a sense of sadness for Harry, knowing that someone out there has created a story that portrays him in such a negative and harmful light. Cedric might even consider taking some sort of action, like talking to Harry about it or trying to get the fanfiction removed if he could, though that would be a complex matter given the nature of fanfiction and the different worlds they live in.
In the fanfiction world, if Snape finds Harry cutting, he might be initially shocked and angry. He could see it as a sign of Harry's inner turmoil. Snape, despite his complex relationship with Harry, might feel a sense of responsibility. He might immediately take steps to stop Harry from further harming himself, perhaps using his magic to heal the cuts. And then he would likely question Harry about why he was doing such a thing, trying to get to the root of the problem.
Draco may first be confused. Fanfiction is a rather strange concept to be singing about. However, as he listens more, he could start to understand the passion behind Harry's singing. This might lead to a moment of self - reflection for Draco. He might wonder if he's been too quick to judge Harry all these years. And perhaps, in a strange turn of events, it could even start to break down some of the barriers between them.
Snape's initial reaction would be one of disbelief. He has his own set of prejudices and ideas, and gay romance fanfiction is far from his realm of understanding. He might snatch the fanfiction away from Harry in a fit of annoyance. But as he sees Harry crying, he might start to wonder what in this strange piece of writing has such an emotional impact on Harry. This could lead to a very awkward and tense moment between them, with Snape not knowing how to handle the situation properly.
In some fanfictions, Snape might be secretly sympathetic. He may see the scars as a reminder of all Harry has been through, which could soften his usually harsh attitude towards Harry, at least for a moment.