Hermione could be the main character. Given her inquisitive nature and love for knowledge, she might be involved in an experiment that causes a DNA mishap. For example, she could be researching a new spell in the library and accidentally triggers a reaction that messes with her DNA. This would be a huge challenge for her as she's always been in control of her studies and actions, and now she has to deal with unexpected changes to her body and abilities.
It could be Neville. He's often underestimated, but in a 'dna mishap' scenario, he could be the one who stumbles upon a hidden part of the Hogwarts grounds where an ancient magic causes his DNA to change. Maybe he becomes more attuned to the plant life around Hogwarts in a very different way, like being able to actually feel what the plants are thinking. This new ability could put him in a position where he has to step up and use it to protect the school or his friends.
Well, it could be about a character in the Harry Potter world who has a DNA mishap due to some dark magic experiment. Maybe they start developing strange powers or characteristics that are not normal in the wizarding world. For example, they could have the ability to communicate with animals in a different way than normal Animagi. This would lead to all sorts of adventures as they try to figure out what happened and how to reverse it, while also dealing with the reactions of their friends and foes in Hogwarts.
It could be an ordinary person who stumbles upon a chemical lab by accident and accidentally causes a mishap. This person then has to deal with the consequences, like facing angry scientists or trying to clean up the mess they've made. Their lack of knowledge about chemicals would add to the drama and humor of the story.
Hermione could be the main character. She's always been curious about knowledge, so she might be the one to stumble upon the idea of a DNA test in the wizarding world. She could use her intelligence to figure out how to perform the test and then discover something amazing about her own family's magical lineage.
It could be Naruto himself. Adding divine dna to his character would make him even more powerful and could lead to new and exciting storylines.
Ron could be the main character in a Harry Potter polyjuice potion mishap fanfiction. Ron is known for his sometimes hasty decisions. He might be so eager to prove himself or get involved in some secret mission that he doesn't follow the potion - making instructions properly. This could lead to a mishap where he transforms into an unexpected person, and then has to navigate through the wizarding world in this new form, trying to hide his identity from his friends and family while also trying to reverse the effects of the potion.
A jealous wizard or witch from the Order of the Phoenix could be the antagonist. They might be envious of Tonks' relationship with Harry or her special abilities. So, when the potion mishap occurs, they try to make the situation worse for her, hoping to get her removed from the Order or at least lose her status among the members.
It could be a new character, like a young Auror who has been assigned as an inspector. He would be fresh out of training and eager to prove himself at Hogwarts. He might be a bit naive at first but quickly learns the ropes and uncovers some interesting things about the school.
It could be a young witch who is just starting to explore her magical abilities outside of Hogwarts. She takes on a babysitting job to earn some extra money and ends up having all sorts of magical adventures with the kids she babysits.
A new character could be the main character. For instance, a Saiyan who has been transported to the Harry Potter universe. This character would have to navigate the strange new world of magic while also dealing with their own Saiyan instincts and powers.
It might also be a descendant of one of the well - known characters from the Harry Potter series. For example, a grandchild of Sirius Black who inherits his rebellious spirit and uses it to fight against the new dark forces as the 'darkslayer'.