Saiyuki is a manga series by Kazuya Minekura which was serialized in G-Fantasy from 1997 to 2002. It spawned multiple manga sequels, anime adaptations, video games and other media. The story is loosely based on the Chinese novel Journey to the West.
Saiyuki is the story of four anti-hero-like heroes: the monk Genjyo Sanzo, the monkey king Son Goku, the half-demon Sha Gojyo, and the man who turned into a demon Cho Hakkai (formerly known as Cho Gonou). They have been dispatched by the Sanbutsushin (the Three Aspects of Buddha, who relay the orders of heaven) to travel to India to stop the possible resurrection of the Ox-Demon-King, Gyumaoh. Along the way they are beset by inept assassins, bad weather, and their own tragic personal pasts. Meanwhile, the villains, two unlikely confidants, Gyokumen Koushou (Gyumaoh’s concubine, a demon) and a mad scientist, Dr. Nii Jianyi (a human), continue their attempts to restore the long-dead king. These experiments, a forbidden mixture of science and magic, spawn the “Minus Wave”, infecting all of the demons in Shangri-La with madness, shattering the fragile peace that once existed between humans and demons.
The Saiyuki manga comprises five separate series. The original series comprised nine volumes, and was serialized in the manga magazine Monthly GFantasy from February 18, 1997 to January 18, 2002. The second series began in June 1999, and was called Saiyuki Gaiden. Saiyuki Gaiden comprised four volumes and ran for ten years in the Japanese shōjo manga magazine Zero Sum Ward.This second series takes place in Heaven, 500 years before the first Saiyuki series. The plot is based around the four main characters of Saiyuki in their past lives, and details exactly what it was they did to get thrown out of heaven. In 2002, a third series was made entitled Saiyuki Reload that lasted 10 volumes long. The third series was serialized in the monthly Japanese Jousei manga magazine Monthly Comic Zero Sum and completed its run in 2009 in the August edition.The third series spun out a fourth series called Saiyuki Reload Blast which is currently being serialized in Monthly Comic Zero Sum. The fifth and final series made titled Saiyuki Ibun started in 2009, and is currently running in Zero Sum Ward. The fifth series follows Priest Koumyou Sanzo in his days before inheriting the Sanzo Title.