In this fanfiction, Peter might have discovered some dark secret about himself or his world. He locks himself away to protect others from it or to come to terms with it on his own. He could be in a world full of magic or superpowers, and this secret is related to that. He needs time alone to understand how to control it or whether to reveal it.
Maybe it's his sister, Mary. Mary could have some idea about why Peter has locked himself away. She might be torn between respecting his privacy and wanting to help him. She could be bringing him food and leaving little notes outside his locked door, trying to communicate with him.
One possible plot development could be that the village is in great danger from an enemy too powerful to defeat directly. Naruto, seeing no other way, seals himself away to act as a last - line - of - defense deterrent. If the enemy tries to completely destroy the village, Naruto's sealed power could be unleashed to counter them.
A possible plotline could be Peter deciding to break away from the Avengers or any big superhero group he's associated with. He might feel that he's not growing as much as he could on his own. So, he sets out to be a solo hero again, facing new challenges without the backup of the group.
One possible theme could be self - reliance. Peter giving himself stitches might show his ability to take care of himself in a difficult situation.
In this type of fanfiction, one possible plot could be that Harry is under extreme mental pressure. Maybe he's constantly haunted by the deaths he has witnessed, like Cedric's death or the losses in the war. The pressure builds to a point where he feels like there's no way out and contemplates shooting himself as a way to end his pain.
One possible plot could be Naruto believing that by joining the Akatsuki, he can change them from the inside. He might think that his influence can stop their more evil plans. For example, he could try to convince them to stop collecting the tailed beasts in a violent way.
In a 'Peter slaps Edmund fanfiction', it could start with a misunderstanding. Edmund is wrongly accused of stealing or lying, and Peter, believing the false information, lashes out and slaps him. The rest of the story could be about the search for the truth, how Edmund feels wronged, and how Peter realizes his mistake. It might also involve the relationship between the two characters being strained at first and then gradually repaired as the truth comes to light.
Maybe Peter punches Steve because of a misunderstanding. For example, Steve might have been wrongly accused of something that Peter holds dear, like endangering his family or friends. In his anger, Peter decides to take matters into his own fists.
Maybe Peter inherits Tony's high - tech gadgets. For example, he could get access to some of Tony's Iron Man tech, which would be a huge deal. This could set him on a new path in his superhero journey, perhaps allowing him to upgrade his own suit or develop new abilities.
Perhaps there is a misunderstanding. In the fanfiction, other characters might have misinterpreted Peter's actions or words, and this has led to an uncomfortable situation for him. As a result, he chooses to distance himself to avoid further conflict.