In some 'Harry Potter sister womb fanfiction', the sister's very existence in the womb could be a prophecy fulfillment. Her birth might be surrounded by strange magical events. For instance, when she was in the womb, all the plants in the vicinity of her mother started to glow, and as she grows, she discovers that she has a special bond with nature magic that was first signaled during her time in the womb.
There could be a lack of widespread 'Harry Potter womb lemon' fanfictions as it's not a common or recognized trope within the mainstream Harry Potter fan community. But generally, in Harry Potter fanfiction, some focus on the romantic relationships of the characters. For instance, Hermione and Draco pairings which deviate from the original pairings in the books and movies.
No, it's not likely to be popular. The concept of 'harry potter womb fanfiction' is rather strange and not in line with the more common and popular themes in Harry Potter fanfiction like adventures, relationships, or exploring different magical abilities. Most fans are interested in stories that are closer to the original spirit of the books or movies, and this seems like a very niche and perhaps off - putting concept for the general Harry Potter fan community.
Then there's their parents. In the fanfiction, the mother could be a key figure as the one carrying the sister in the womb. Her experiences during pregnancy might be detailed, like any strange feelings or dreams she had. And the father, who might be involved in protecting the family during this time when the sister is in the womb. Their family bond is often an important aspect in these stories.
I'm not entirely sure specifically what 'harry potter womb fanfiction' is about as it's not a common or official part of the Harry Potter franchise. It might be some very niche, non - canonical fan - created stories that could involve strange or unorthodox concepts related to the idea of a 'womb' within the Harry Potter universe. However, it could also potentially be something misnamed or not really related to what it seems at first glance.
A really engaging fanfiction might explore the relationship between Harry and his sister during the Triwizard Tournament. His sister could be involved in some behind - the - scenes events that end up affecting the outcome of the tournament. Maybe she has a connection to one of the champions or discovers a plot to rig the tournament and she and Harry have to work together to stop it.
One interesting 'Harry Potter x Twin Sister' fanfiction could be about their adventures together at Hogwarts that are not fully explored in the original books. For example, they might discover a hidden chamber in the castle and have to work together to solve the mystery within it.
I have no idea. Such a description seems rather odd and might not lead to appropriate or positive content.
You could also join some Harry Potter fanfiction groups or forums. Post a query about 'Harry Potter womb lemon' fanfiction. There might be some die - hard fans who have come across something related or might be able to give you some leads on how to find or even create such a fanfiction if it doesn't exist already. But remember to follow the group rules and etiquette.
One interesting plotline could be the twin sister having a unique magical ability that Harry doesn't. For example, she might be able to communicate with magical creatures in a way no one else can. This could lead to her getting involved in adventures that are separate from Harry's at Hogwarts, but still end up being connected in some way, like when she discovers a secret about a creature that is related to a dark wizard who is also after Harry.
In some fanfictions, Harry's sister might be sorted into a different house than him, like Slytherin. This would create a lot of internal conflict within the family as well as at Hogwarts. It could lead to a situation where Harry has to defend his sister against the prejudices of his friends. Or perhaps she has a prophecy related to her that ties into Harry's own destiny, and they have to figure out how to fulfill both prophecies without sacrificing one another.