Kyo Kara Maoh! Shin Makoku no Kyuujitsu [Limited Box] Japan

Kyo Kara Maoh!, is a series of Japanese light novels written by Tomo Takabayashi and illustrated by Temari Matsumoto. The story follows the adventures of Yuri Shibuya, an average 15-year old Japanese high school student, who is suddenly transported to another world where he is told that he is now the king of demons.