Often, it's Stiles' character traits. His awkwardness and quick - wittedness can be really endearing. For example, when he's trying to flirt with someone and ends up saying the silliest things. It's also how he interacts with other characters. His loyalty to his friends makes for some really sweet moments in fanfiction.
There's a fanfic called 'Stiles: The Adorable Hero'. In this story, Stiles is portrayed as this clumsy but extremely lovable character. He has a habit of getting into hilarious yet heart - warming situations. For example, he tries to organize a surprise party for his friends but everything goes wrong in the most comical way, yet it still ends up being an adorable disaster.
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.
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.
Well, often in these fanfictions, Stiles becomes more confident. His physical appearance might also change, like he could start dressing better or have a new haircut that gives him a 'hot' look. For example, he might start wearing more stylish clothes that show off his personality.
Well, the characters being in - character and showing their softer sides can make it adorable. For example, seeing Naruto's innocent love for ramen in a cute way, like he daydreams about different ramen flavors while on a mission.
Well, usually in 'percy is adorable fanfiction', Percy is often depicted as innocent. For example, he might get into harmless little misadventures that are more cute than serious.
Well, Naruto has that goofy side to him that is just so cute in fanfiction. He might make silly mistakes or get overly excited about simple things like ramen. His positive attitude even in the face of great difficulties also adds to his adorableness. He's like a ray of sunshine that can brighten up any story.
Often, it will show Luffy's innocent side. For example, his child - like wonder at new things he discovers on his adventures. It might also focus on his relationships with his crewmates in a really heart - warming way, like how he always manages to cheer them up when they're down.
He is usually shown to have a soft side. Despite his reputation as a trickster, he can be very kind and gentle. This could be seen when he takes care of a wounded animal or helps a lost child find their way home. His actions in these situations are really endearing and show his adorable nature.