Kyo Kara Maoh! Shin Makoku no Kyuujitsu was a PS2 game released September 27, 2007. There were two versions released. The normal game and a limited box which included two figures, a script book and a drama cd.
This game picks up where the anime has left off. After Yuuri interrupted the the ambitious moves of the human states against the demon country by sealing all four magical boxes, peace was achieved. But only for short while.
Back in modern day Japan, Yuuri is oblivious of what would happen in the world where he rules as a king. Instead, he spends everyday arguing with his brother for installing dating games on his computer without his consent, and going out with his long time friend. During a trip to the zoo, he realized what he could do for his country.