Saiyuki

In the mystical world of Shangri-la, demons and humans live side by side, watched over by a parthenon of ancient Chinese gods. But when normally-civilized demons start to go berserk, the gods require the services of Genjou Sanzo - a Buddhist priest with a magical gun, an evil-banishing scripture and a take-no-prisoners attitude. Aided by the ancient monkey god Son Goku, the half-demon Sha Gojyo and the demon exterminator Cho Hakkai, he sets off on a treacherous journey westward, with armies of demons, dark mages and angry gods all standing in his way...