When the students and disciples of Mount Cae eventually depart the safe haven after completing their training, they always go in pairs of two.
One of them is the brawns, specializing in numerous fighting techniques while the second is the brain of the operation, specializing in various ranged skills and arts along with the task of being the physical vessel for the 'Book of Demons'.
The 'Book of Demons' is a living entity, an artifact created from the flesh, bones, and skin of heinous and wicked humans that have led lives full of corruption and wickedness.
It takes the shape of a normal book with a thick leather cover but after being inscribed by countless various depictions of all the different types of demonic beings that walk the mortal plane, it takes on an unholy life of its own.
It is done this way because any knowledge related to demonic beings gives power to them and could even act as a gate for them to enter the physical realm by the mere mentioning of their names or the imagining of their true forms, such is their power.
And since the Book of Demons contains vast knowledge related to such entities, it has to be hidden and protected from any prying and unprepared eyes that happen to glance upon its contents, lest they risk themselves becoming tainted.
The Book of Demons bonds with a living carrier that is pure of heart and experienced in the ways of spiritual arts of Mount Cae and from then onwards, its contents can only be viewed by that vessel and whoever it gives permission to.
It holds the majority of substantiated and authentic information regarding numerous demonic entities, their habits, signs, forms, and ways of dealing with them, if there are any.
Yet everything that is known about the creatures known as "Puer" comes from secondary sources. All incidents related to the actual creatures are hidden away in the flooded depths of Mount Cae's internal library, protected by ancient spirit beasts belonging to the First Master himself…or at least that's how the stories go.
The Book of Demons mentions the following information about them:
They are born when a chosen being is selected by a powerful demon overlord. As long as this so-called 'chosen one' exists, they cannot die either.
They take physical form from a depraved and twisted follower of the associated demonic overlord and their first form is always an inverted four-legged creature. Once their evolution is complete, some Puer have even been known to develop the ability to shapeshift in some instances.
Their first and foremost objective is to protect the interests of the 'chosen one', whatever they may be, and in doing so elevate themselves to a higher level of demonic beings.
***
Zou Huan stood some 80 meters away, hiding behind the rubble of what looked to be a warehouse.
In front of him, the fight between Hao Xuan and the Puer was nearing its end. Hao Xuan had numerous wounds on himself yet he didn't let the Puer get more than a few meters away.
It was clear that both of them were running on fumes since they were using their physical bodies to determine the winner. Hao Xuan stuck to it like glue, tearing chunks of black and red flesh off of its body whenever it tried to chase after a random undead to try and eat it for replenishment.
If Zou Huan didn't know any better he would have concluded that Hao Xuan was the monster in this scenario. Hao Xuan chased after the Puer like a rabid dog as a series of blue lights continuously pulsed under his skin.
The duration between each pulse continued to lessen until it 'popped', resulting in an explosion of a blue field that covered the Puer as well.
Zou Huan had to look away when he finally saw Hao Xuan bite off the extra appendage coming out of the Puer's back/abdomen and swallow it whole.
A sudden explosion took place inside Hao Xuan's body that was audible even to Zou Huan from such a distance away and he could feel something inside Hao Xuan change.
The Puer let out a heart-wrenching roar before unleashing a beam of red light aimed straight for Hao Xuan's chest.
Hao Xuan was far too close to dodge it completely but he reacted quickly enough to bring both his arms in front of him. The beam impacted with Hao Xuan's body and sent him flying into the distance, too far for even Zou Huan to see.
Needless to say, Zou Huan thought Hao Xuan to be dead and locked his gaze on the Puer that was severely injured. It let out another roar, sounding like a mix between a human and a goat.
The undead that were scurrying in the distance ran towards it and started eating it. The Puer didn't try to fight back, letting them gnaw off of its body parts bit by bit until there was nothing left.
Zou Huan stayed and watched until the very end, when even the last bone was swallowed by an undead and they scampered off in different directions, leaving him stumped.
