well maybe it's not a costume because she looks more confused than excited
not that you'd be able to tell what she'd be dressing up as
except maybe some weird generic animu character because hey, blue hair
that's a thing
why is she holding a giant key that's mega weird what a weirdo it's not a weapon why are you holding it like that
she walks out of the misty woods and reaches the castle. there's an odd sort of hope in her eyes as she first looks at it, then sighs and lowers her head.]