"Claymore"

    The dark fantasy anime and manga Claymore describes a world that is tormented by human-devouring monsters called youma. They are twice as dangerous, because they can easily blend in human society. A group of female warriors belonging to secret order, who are called Claymores, devote their whole life to track and kill the monsters.
    I love the series, both manga and anime. It's beautiful and main protagonist, Clare, is really inspiring, and her final goal epic and dark.