Twelve Kingdoms. Book 1. Shadow of the Moon

Twelve Kingdoms – a magical world existing on the edge of our reality. Yoko Nakajima, an ordinary Japanese high school girl, is destined to become its guest… and one of the main characters of this story. On one very ordinary day, Yokos school is attacked by monsters, and then a mysterious young man from another world appears. And he claims that Yoko is the heir to the Kingdom of Kei, who must fight for her throne...