Go Dougan

Go Dougan (呉道雁) is the main antagonist of Saiyuki Requiem. He was once a young acolytes working a personal attendant to Sanzo.

Personality
When Dougan first appeared before Sanzo as a young boy, he was shy and introverted. After being assigned as Sanzo's personal attendant, he proved himself to be extremely loyal and faithful, that it brought him out of his shell. He was infatuated with Sanzo and adores him .However, because of jealousy to that he harbored for Sanzo's relationship with Goku, and his friendship with the sinner Hakkia and philanderer Gojyo, he drove himself to the point of obsession. He became fixated on the idea that he wasn't good enough for Sanzo. He wanted to become stronger in the hope that Sanzo would take him with him and use him. His most fondest wish was to be useful to Sanzo.

Despite his solitude training in the mountains and the three years he spent refining his skills, he returned to Keiun Temple to find that Sanzo had left on a journey with the very youkai that he envied. He became violent and his goals became more twisted. He became homicidal and killed thousands of youkai so that he could become a demon as Hakkai had been. He killed a Hanyou child and soaked his hair in the blood until it was dyed with the color. Claiming the castle the estate of the dead Houmaoh, who he killed. He made himself lord of the castle and waited for Sanzo and company to come.

Appearance
In his youth, Dougan had wavy teal colored hair and always wore it in a long braid down his back. He has grey-brown eyes and thin wire-frame glassed. He also had freckles that covered his upper cheek bones and the bridge of his nose. As a youth he wore the typical short robes provided for the acolyte. When he was older he wore training robes during his time in the mountains.

When he started his search for Sanzo, he stained his long hair with the blood of a hanyou and dawned a black Chinese robes with a gold dragon pattern on it. And then after becoming a youaki his demon mark appeared; crossing over his nose where his childhood freckles had been. He wore his hair loose and wild and forsook his glasses, as he didn't need them anymore. He also wore a strange bird mask that hid his face with a main of feathers that covered his hair.

Backstory
Dougan was an orphan and he was assigned as Sanzo's personal attendant. Sanzo asked what happened to his face and Dougan replied that he is being bullied because he's just an orphan. As Sanzo stated that he and Dougan are the same. Dougan began to look up to Sanzo as he became infatuated. He did everything just to notice by Sanzo. He asked Sanzo if he could go with him in his every task. However, Sanzo disapproved because he has Goku and he doesn't need to protect him. He later became jealous of Goku, Hakkai and Gojyo.

From that day, he became determined that he will prove to Sanzo that he will be strong and hoping that someday, Sanzo will have a use for him on his mission. He left the temple, underwent training and he returned after years. The monks told him that Sanzo was no longer in the temple. As he thought that he was left behind again. Dougan ran away again and promising his self that he will show Sanzo how strong he is. He learned like Goku being loyal, he killed a thousand demons in one-night and became a youkai like Hakkai and he dyed his hair red like to be Gojyo, aspiring that he will assist Sanzo.

After years, he waited in the castle where he killed thousand of youkai. Making Princess Houran his servant and waiting for the day that Sanzo would show that he could finally show how strong he is.

In the end, he was defeated by the Sanzo party. Before Sanzo killed him, he reminisces the past when he was with Dougan. When Dougan was asking Sanzo if he can take the paper plane. Sanzo replied to take it and saying that "You can only fly those across the blue sky.". Dougan asked why and Sanzo replied "That's a good question. I'm still searching for an answer.".

After Sanzo shoots Dougan's body, his body fade away like ashes and seeing a paper plane with a hole from Sanzo's bullet. Meanwhile, Lirin in the top of the mountain found a paper plane and flew it in the west across the blue sky. Sanzo saw the paper plane flying. The paper plane represents Dougan's death and continuing their journey to the west.

Trivia

 * Go Dougan is supposed to have been around Sanzo since before Sanzo picked up Goku. He was also there when Sanzo apprehended Cho Gonou. Yet, it all the flashbacks in the anime, he is never seen or mentioned. According to the head writer of the movie, Katsuyuki Sumisawa, as well as Minekura Kazuya (who helped in scripting the plot), this is entirely by design as he is meant to be an inconsequential character that existed in the background of the Sanzo-Ikkou's story.
 * It's also unknown how old Go Dougan is. He was prepubescent when he met Sanzo, who was no longer travelling. It stands to reason, then, that Go Dougan was still roughly that old when Sanzo picked up Goku. Yet, he appears in the movie as almost a young adult.