Well, in some stories, it could be a family curse that has been passed down through generations. Maybe her ancestors made a deal with dark forces long ago and as a result, she is doomed to turn into a werewolf. Also, it could be related to a place. For example, if she lives in an area that has a strong connection to werewolf lore, the energy of the land could somehow trigger the transformation. And of course, as mentioned before, a werewolf bite is a classic cause.
Imagine a girl who is an outcast in her town. She has a fascination with the legends of werewolves. One day, she meets a strange old woman who gives her a charm. Unbeknownst to her, the charm has the power to transform her into a werewolf. When she becomes a werewolf, she finds that she can communicate with the animals in the forest. She uses this ability to learn about a coming danger to her town. She then has to convince the townspeople to believe her, even though she is now a werewolf, so they can all prepare for the danger.
Once upon a time, there was a girl named Lily. One night, while she was walking in the forest, she was bitten by a strange wolf. The next full moon, she started to feel strange. Her body began to change. Hair grew all over her, her teeth became sharp, and she turned into a werewolf. She was terrified at first, but as time passed, she learned to control her new form to some extent.
In a girl - werewolf TF (transformation) story, perhaps the girl could be bitten by the werewolf and start to transform herself. She might experience strange physical changes like growing fur, getting sharper teeth and nails. And she would have to deal with the new instincts that come with being part - werewolf, such as a craving for raw meat and a heightened sense of smell.
In some Twilight fanfics, a werewolf face - licking a girl could be a sign of an intense connection. It might be a way to show the werewolf's protectiveness or a unique form of affection within the context of the story. It could also be a creative and somewhat strange way the author has chosen to explore the relationship between the werewolf character and the girl character.
To write such a scene, start with the werewolf's perspective. What is it thinking and feeling at that moment? Is it driven by a primal urge or a more tender emotion? Then, when it comes to the act of face - licking, use vivid language. For example, 'The werewolf's warm tongue flicked out, tracing a gentle path along the girl's smooth cheek.' After that, explore the girl's response. Does she pull away in surprise or lean into it? You also need to consider how this scene fits into the overall plot of the fanfic and what it will lead to in the future relationship between the two characters.
In the world of Harry Potter fanfiction, there is a vast variety of stories. However, the idea of a 'giant werewolf face lick girl' is not a common or canonical theme. Fanfic usually adheres to the general spirit of the original series, which is about adventure, mystery, and the growth of the characters. So it's very unlikely to find such a plot in mainstream fanfic.
I recommend the book "Cold Boy's Pet Werewolf" to you! It was a story about a college student who became friends with a vampire after meeting a werewolf. One of the plots was that the werewolf turned into a wolf and saved a girl. This book has also been published in physical form. I believe you will like it. I hope you like this fairy's recommendation. Muah ~😗
It could be a tale of a girl with a unique werewolf curse that causes her eyes to bleed when she transforms or experiences intense emotions related to her werewolf nature.