 The episode "Chokyuukai and the Plundered Brides" features a boar  youkai named Chokyuukai and his servants, a kappa named Sa Gojyo and  a monkey youkai named Son Goku. These three, and the "master" to  whom Chokyuukai briefly refers, are figures from Journey to the  West, a famous work of Chinese literature about a Buddhist monks  pilgrimage to India. Journey to the West was itself adapted into the  anime series "Gensomaden Saiyuki."