Saiyuki Gaiden: Episode 01

This is the summary of the first episode of Saiyuki Gaiden OVA.

Summary
Heaven, where the gods live. In that world where ‘death’ doesn't even exist, Konzen Douji spent his days, bored. However, his life begins to change with the introduction of a golden-eyed boy. Standing at Kanzeon Bosatsu’s side, they said he was born from the Lower World from a stone. Konzen was charged with looking after the innocent boy. He began to sense a change in his life, even as he was irritated with being toyed with. The boy became friends with the young War Prince, Nataku. The boy later receives the name “Goku” from Konzen, and they became close with Tenpou and Kenren of Heaven’s Western Army.

Shocked by the tragic death of Nataku, Goku's true raw power was released in the form of the "Seiten Taisei" when his youkai power limiter, his golden diadem, was broken. A massacre occurred and those in the area were overwhelmed by his destructive power. Kanzeon Bosatsu knocked the beast out, but Konzen Douji stepped in to stop her. However, for protecting Goku, Konzen, Kenren, and Tenpou were made enemies of Heaven. They took their commanding officer, the Dragon King of the Western Ocean, Goujun, hostage and they attempted to flee to the Lower World. The four of them--Konzen, Goku, Kenren and Tenpou--promised that “We’ll always be together,” “Even if we get separated, we’ll meet again beneath the sakura in the Lower World.” 

The four headed for the only path connecting Heaven and the Lower World: the Dimension Gate. They released Goujun as Tenpou and Kenren gave their report to him telling him that they will resign in their positions. The four of them entered the Heavenly Palace and encountered Enrai’s unit, Western Army Second Unit, but thanks to the Western Army First Unit who barged in and fight to help their superiors escape. In Tenpou’s last order, he ordered them to kill all Second Unit in the room and do not let a single person who'd seen them leave alive. After Tenpou and Kenren left, Rikuou encouraged his fellow First Unit that they will complete the mission and it will be their final battle.