Ceres: Celestial Legend, Vol. 1: Aya

This manga is described as horror and that fits because it is much darker than Yuu Watase's other series. There is a lot of violence and this is displayed clearly from the vivid illustrations to the story itself it is rated correctly for older teens. But it is also a very good story there is folklore, fantasy, scifi and definitely romance because this is after all a shojo manga. Give it a read, I thought it was a a very good story that had me laughing and cringing and crying.