His best friend could discover it. Since they are so close, they might notice something different about Stiles that makes them suspect he's actually a girl.
A frequently seen theme is the reaction of the other characters. Some might be shocked, while others quickly adapt. Also, the theme of facing challenges differently as a girl comes up often. In some fanfictions, she might face more discrimination or different types of expectations.
Well, it could be that Stiles is secretly a girl and in the fanfiction, this secret is slowly revealed as he falls in love with someone. And the person he loves starts to notice little things that don't quite add up with his supposed male identity, like his more delicate features or his different style of communication.
Well, relationships are a big theme. Romantic relationships change when it's revealed that Stiles is a girl. Also, friendships are put to the test. Some friends might be more accepting than others. And there's often a theme of secrecy and the consequences of hiding one's true identity for so long. In these fanfictions, Stiles may have been hiding her gender to fit in or for safety reasons, and when the truth comes out, it has a ripple effect on the whole story.
Well, there's a fanfiction called 'Stiles, the Unseen Girl'. In this story, Stiles has been hiding her true gender for various reasons, like protection. It shows how she navigates her friendships and the challenges that come with revealing her real self. There are also some stories where her being a girl adds a whole new dynamic to the romantic relationships in the story.
There's also 'Stiles: Girl Version' where the story focuses on her struggles and strengths as a girl in a world full of supernatural challenges. It's a really engaging read as it gives a new perspective on Stiles' character.
In Stiles werewolf fanfiction, Stiles is often depicted as intelligent. He uses his smarts to navigate the complex world of werewolves. For example, he might figure out a way to break a werewolf curse using his knowledge.
One possible plot could be Stiles' struggle to adapt to his new female body. He might have to deal with different social expectations and how his friends react to his new appearance. Another plot could involve Stiles trying to find a way to turn back into his male self while facing various challenges along the way.
There might be a jealous friend or acquaintance who feels that Stiles, as a girl, is getting too much attention. This person could then start spreading rumors or causing trouble for Stiles in an attempt to bring her down.
Another character he could interact with is Thor. Thor's otherworldly nature and his powerful abilities would be quite a contrast to Stiles. Maybe Stiles could help Thor understand some earthly concepts while Thor could teach Stiles about Asgardian culture and power.