Transforming Succubus: Almost Doomsday

The apocalypse was nigh.
A few humans awakened as pioneers. They were granted the privilege to step forward and travel to different "versions" of the world.
Their duty was to venture into these various versions of the world to obtain power, artifacts, and information and then return to the original world to prevent the disaster of the apocalypse.
But the disgrace of the pioneers — different pioneer Zhou Baiyu — made an immense contribution to all of humanity. Through his unremitting efforts... the apocalypse eventually did not come to pass.
At the same time, he also made a tremendous contribution to the demons. Through his unremitting efforts... it was very nearly, by a hair's breadth, that the apocalypse descended.
The story... must start with his transformation of the succubus.