Goku Son

Height: 162 cm (5'4")

Perpetually hungry, energetic, and playful, Goku is Sanzo's constant compansion—viewing him as the "sun" around which his world revolves. He is neither a demon nor human, but is a heretic born from the Earth itself. Along with his incredible strength and speed, he uses his nyoibou (extendable staff) to fight demons in battle. Tasked by the Sanbutsushin (Three Aspects) and Kanzeon Bosatsu to accompany Sanzo on his journey, Goku is often seen trading insults with Gojyo or fighting with him over food.

Backstory:

(Source: Saiyuki.wikia & Saiyuki Reload Graffiti booklet)