Simon Grey and the Curse of the Dragon God

Japan, 17th century: Simon Grey and Oyuki Winter, born with the ability to see the spirit world, are given a rare chance to visit an enchanted undersea kingdom. But this gift soon becomes a curse, as they return to find themselves stranded in a country where their presence is a crime. Their only hope of survival lies with the mystical young warrior Amakusa Shiro, leader of a ragtag band of rebels against a tyrannical lord. With samurai, monsters, and magicians attacking them from all sides, even the new powers they gain from their allies among the yokai may not be enough to save them...