Patalliro Saiyuki!.

Genjō Sanzō is a Buddhist monk sent by the Emperor on a journey to find the sacred Buddhist scriptures. One day, Sanzō meets an Earth Deity who tells him that Buddha has sent him a disciple: the mischievous Monkey Deity Son Goku, who was sealed inside of a mountain for five hundred years after wreaking havoc in Heaven! Together with the alcohol-loving playboy Cho Hakkai; the heavenly army General Sha Gojyō; and their horse, the Dragon Crown Prince Ryūba; there are plenty of adventures to be had.