She can become the hero. Instead of being the victim, she uses her wits and strength (both physical and mental) to defeat the evil. For example, if it's a haunted house story, she might figure out the secret to banishing the ghost while the others are panicking.
She could be the one in control all along. Maybe she was the one who accidentally summoned the horror, but not in a malicious way. And now she has to use her unique knowledge and skills (that others underestimated) to fix the situation. Like she has a special bond with an entity that she can use to her advantage. She can also change the perception of beauty and strength. By showing that she is not defined by her size and can be just as brave and capable as any other character in the story.
She can be shown as a misfit. This might isolate her from other characters, and when the scary events start to unfold, she has no one to turn to or no one believes her warnings. For instance, in a story set in a school, the fat girl might be bullied and then be the only one to sense the presence of a malevolent spirit, but her classmates just laugh at her.
It subverts it by changing Draco's status. In the original, he's a bully from a wealthy family. Here, as a slave, he's at the bottom of the social ladder. This completely alters his character arc and the way other characters interact with him.
One common trope is that she might be the first victim. In many scary stories, the character who doesn't fit the 'typical' body standard is often singled out as an easy target for the antagonist. Another could be that she is misjudged. People in the story might assume she is weak or helpless because of her size, but she could turn out to be very strong or resourceful when facing the horror. Also, she could be a red herring. The story might make you think she is the source of the horror due to her appearance, but in fact, she is just another victim.
Girl gets fat stories can be inspiring because they often depict a journey of transformation. The girl might start from a place of low self - esteem due to her weight but through hard work, whether it's changing her eating habits or starting to exercise, she can achieve a more positive self - image. This process of growth and self - improvement can inspire others who are also facing body - related issues. Also, these stories can make people more aware of the importance of body positivity and acceptance, not just for those who are overweight but for everyone in general.
She can start by changing her diet. Cut down on high - calorie and junk foods, and increase the intake of fruits, vegetables, and lean proteins like chicken and fish. For example, instead of having a bag of chips, she can have a piece of fruit.
One common trope is that the fat girl might be the first victim. In many horror stories, the character who doesn't fit the typical 'attractive' or 'athletic' stereotype is targeted first. For example, she could be lured into a haunted house by a seemingly friendly entity and then meet a terrifying end.
The mpreg aspect in these fanfics adds a whole new layer of family and relationship dynamics. In the original 'Harry Potter' story, family was mainly about Harry's parents and his friends as a sort of surrogate family. Here, the idea of Harry and Voldemort having a family together is a radical departure. It makes the story more about personal relationships and less about the battle between good and evil in the traditional sense. For example, they have to consider how to raise a child together, which is not something you'd expect in the original narrative.
It changes the expected narrative by steering away from war - related themes. So we don't expect military conflicts or battle scenes.
One way could be by finding a hidden loophole or weakness in the curse's structure and exploiting it.
One way to subvert a love story is to have the main characters face insurmountable obstacles that prevent a straightforward happy ending. You could also play with the idea of love at first sight not working out or have one of the characters have a sudden change of heart for an unconventional reason. These elements can add a fresh and unexpected dimension to the story.