The nameless demon was taken into the depths of the castle of Obelisk by the same butler who had brought him here.
The wizened butler spoke, "You would do well not to get too complacent. This is perhaps the greatest time for you to train your weapon skills, when your body has still not adapted to the density of the demonic essence in the air here."
"I was not aware that your intellect had advanced to the point of proper communication, or I would have treated you as fully sentient."
The nameless demon lets out a small inquiring noise.
Feeling it's intent, the butler says, "Yes, as you aren't used to the demonic essence here, whenever you get injured, your body will reflexively heal it with the essence in the air."
The nameless demon scratched a bloody furrow within it's skin to test the theory, and it turned out be true.
The demon watched as the surrouding essence flooded to the wound and quickly knit back the muscles and skin to it's previous unblemished state.
The old butler laughed and said, "Eager, aren't you? Well, cease such actions until you are called for training, as repeated regeneration will cause you to adapt faster."
The butler stopped in front of a room and gestured for the nameless demon to enter.
As the nameless entered the room, he was awestruck by the sheer size of it.
And the need for such a size was quickly made visible as a demon with wings could be seen flapping it's way across the room.
"Welcome to the Grand Library, young one."
"You should be honoured. Never before has there been a demon not even at the level of a Duke, who has seen the inside of this library."
I recalled the Path of Ascension for demons from Jace's memory, but I decided to ask about it anyway, to maintain an illusion of ignorance.
Unperturbed, the butler explained, "After conquering the first layer of Hell, where you were born, and gaining the approval of the Baronet rank demon stationed there, you gain the title of a Baronet yourself."
"For the second layer, you receive the title of Baron."
"For the third layer, Viscount."
"For the fourth, fifth and sixth layers, you become a Count, Marquis, and Duke correspondingly."
"The seventh layer's ascension grants the title of Demon Prince."
"The eighth layer's ascension grants the title of Demon King, which is what the Patriarch has achieved."
"And the final layer's ascension grants the title of Devil, as is our Lord Belphegor."
The nameless demon looked around at the sheer scale, the awe of seeing it in person far surpassing simply reading about it.
The butler continued as they walked through the labyrinthine library, "Additionally, some demons can develop their own souls through various methods."
"Perhaps one could devour enough human or divine souls to form their own."
"Or it may form due to one's innate talent, like the Margit clan living near the Styx."
"While a normal soul facilitates humans to use magic, be sapient, and overall exist, a soul is not a necessary part of life for a demon. Especially since we devour other souls."
"A demon's soul surrounds their Sin, and empowers it. Even now, you should feel your Sin to be greater than before."
"This allows you to gain more abilities related to your Sin, even without climbing the Path of Ascension. It's immensely useful for a young demon like yourself, not so much for one's like the Patriarch and myself."
This caused the nameless one to have a mixture of feelings.
On one hand, his soul was completely pure and separated from his Sin by whatever entity had tried to stuff Jace's soul into his body.
Due to the memories of the novel he had, there were some opportunities that were useful only for those with a 'pure' soul.
However, these opportunities were far into the future. He was missing out on the supposed increase in abilities he could have gotten now, for some vague rewards in an uncertain future.
'Just what was Jace thinking when he wished for this?'
The little demon couldn't do much except accept it, and pray that Jace's third wish, the special ability he had wished for, would be enough to hide the discrepancies in his soul.
The nameless demon made a few more unintelligible screeches, but the butler seemed to understand.
"Your demonic essence is your being. It is what constitutes your 'self'."
"The flesh you are made up of."
"The energy you use when casting spells or Sin abilities."
"Everything is demonic essence."
"An increase in demonic essence at birth, means stronger demons, which is why the Patriarch powers the False Suns in the first layer fragments owned by us, with his own demonic essence."
"As the latest batches of demons making their way through the layers were of.....inadequate quality, I was sent to examine the facilities in the first layer."
The nameless realized just how fortunate, or misfortunate he had been.
To arrive at the facility at the exact time the butler had.
To be noticed by the butler in a positive way.
To be taken in by the Sloth faction.
It was almost too perfect.
The butler said, "Listen closely. While the enhanced demonic essence of this layer will make you evolve much faster than usual to a Baronet rank demon, you should train yourself as much as possible with whatever weapon you wish to use before the evolution begins."
"When the evolution is complete, your new form will be slightly better formed to wield that weapon."
"If you manage to gain a Mastery, then- No, perhaps that's too much to ask of you."
The nameless had not known of this side of demon evolutions, but then again, the protagonist of the novel had been a human.
The greatest mention of demons was during the Hell Survival arc, and that was not too useful for my current situation, especially since he wasn't on the first few layers anymore.
They finally made it to the other side of the library after an hour or two of walking.
Through another series of corridors, they finally arrived at a room that was close to the outskirts of the castle.
The butler stated, "Enter, and choose whatever weapon resonates with your soul."
"Keep in mind, however, any weapon you choose, I will be teaching you about it very throughly."
With that ominous warning, the demon entered the room full of practice weapons.
The butler's voice came from outside, "Ignore the practice weapons. Head deeper into the Mithril weapon section."
Mithril was common in the Nine Hells, enough for the mass production of weapons.
The nameless demon removed the exotic choices like tridents, scythes, swordbreakers and the like first.
Then the ones that required much more skill than others, like whips, rope darts etc.
Then went the ones that required specific builds that went against the demon's future plans, like warhammers and maces.
The final choices came down to a spear, a sword, an axe, a sabre and a shield.
After considering what all artifacts were actually feasible for the demon to get in the future, he made his choice.