A really interesting plot point could be the love interests that develop for Harry in his new form. Since he's now a girl, perhaps some characters who never showed interest before start to notice him in a different way. Neville, for instance, might start to have a little crush on this new Harry. And Draco himself could be conflicted as he might start to develop feelings for Harry which would completely change the dynamic of their rivalry.
One interesting plot point could be the two rivals being forced to work together during detention. They might start to see each other in a different light. For example, they could discover they both have a passion for a certain subject like potions, which they didn't know before because of their rivalry. Another plot point might be the challenges they face during the detention tasks. It could be something magical and dangerous that they have to overcome together, which builds an unexpected bond between them.
One possible plot twist could be that Draco, after turning Harry into a girl, starts to have feelings for this new version of Harry that he didn't expect. He might struggle with his new - found emotions as he was previously an adversary. Another twist could be that Harry, as a girl, discovers new magical abilities that were dormant before. This could change the power dynamics in the wizarding world. And perhaps, the whole Hogwarts community has to adjust to Harry's new gender, which could lead to both humorous and serious situations as people's preconceived notions are challenged.
One idea could be that as a girl, Harry has to face different social expectations at Hogwarts. For example, she might be pressured to conform more to traditional female roles in magic, like in potions classes being expected to focus on more 'domestic' spells. Another plot could involve her relationships with male and female friends changing. Maybe Ron has a different kind of protective instinct towards her, and Hermione becomes even closer as they bond over the unique experience of being a girl in a male - dominated magical world.
One interesting plot point could be how Hiccup adjusts to the new physical form. For example, he might struggle with the different clothing styles and social expectations for girls in his world. Another could be the reactions of his friends. Some might be shocked at first, while others could be more accepting and help him through the transition. There could also be a plot point about how this change affects his relationship with Toothless. Maybe Toothless initially doesn't recognize him and Hiccup has to find new ways to bond with his dragon.
The main characters are Harry and Draco. Harry, now in a female form, is the center of the story as he experiences a whole new way of life at Hogwarts. Draco, on the other hand, is the catalyst for this change. He is likely to be a central figure as he either tries to reverse what he's done or deal with the new situation he has created. There may also be other important characters like Hermione and Ron, who are Harry's friends and will be involved in his new journey.
Well, one interesting plot point could be how Harry adapts to his new snake form. Maybe he discovers new abilities like slithering really fast or having a heightened sense of smell. Another could be how his friends react. Do they recognize him right away or is it a struggle? And then there's the whole aspect of how he communicates in his snake form. Does he hiss in a way that can be understood by other magical creatures?
Well, perhaps in the fanfic, a magic spell gone wrong turns Harry into a girl. He then discovers that being a girl in the wizarding world gives him a whole new perspective. He could start noticing things he never did before, like the way female wizards are treated in certain classes or by certain teachers. His relationships with other characters also change. For example, his relationship with Ginny could become more of a sisterly bond at first as he adjusts to his new form.
Well, in this type of fanfiction, a plot point could be the change in Draco's behavior. Since he is under the Imperious Curse, his actions might seem out of character. Harry might notice that Draco is doing things that he wouldn't normally do. For example, Draco might be acting more subservient or being forced to target Harry in a more malicious way than before. This would make Harry start to suspect something is wrong. Also, there could be a plot point where Harry has to convince his friends, like Hermione and Ron, that Draco is not acting of his own free will. They might be skeptical at first, but as Harry uncovers more evidence, they come around to help him figure out how to break the curse on Draco.
A great plot point could be that the potions accident results in them being able to read each other's minds. They suddenly have access to each other's deepest thoughts and secrets. This makes them extremely uncomfortable at first, but as they start to understand each other better, they form an unlikely bond. For example, Harry discovers that Draco is under a lot of pressure from his family, and Draco realizes that Harry has his own insecurities despite being the 'Chosen One'.
One interesting plot point could be the reactions of their friends. Harry's friends might be really confused seeing him with Draco's tie, and Draco's cronies might be equally shocked. It could lead to some humorous exchanges as they try to figure out what's going on.