Stravaganza: Isai no Hime

Humans live mostly behind safe walls, protected from the many non-human creatures outside. In this kingdom's walled capital city of Mitera lives an unusual young warrior woman known as Claria. The story begins as she takes a potentially deadly walk alone in the woods, encountering various dangerous creatures—most notably a lizardman that treats her surprisingly kindly. But what no one knows about Claria is that she is secretly this kingdom's ruler, Queen Vivian!

(Source: MangaHelpers)