A couple days after Chojusen started his new life as Issei Hyoudou, he managed to unseal a part of his original skills. However, it seemed like all his skills now took on the prefix of "Demonic." Furthermore, he had to start training them all from scratch. However, he would at least now have something to rely on if he ever got mixed up in a fight.
Currently Issei only had access to the following skills: Demonic Yang Rebirth, Demonic Gravity, and Demonic Elemental Coating. He had only been trying to use his energy to make training more efficient and as a result, only these skills were unlocked; Elemental coating was unlocked as a result of his experiments with the new world's system of energy. It seemed that the skills after being powered by demonic magic would be much stronger than their counterparts when made up of only chakra.
On the fourth night after making the ascension, Issei had an odd dream; at that time, his Yang Rebirth was still sealed. He dreamt of a night with his three wives back in his home universe; even though he knew the true body was probably at work as he dreamt, since he had his connection removed, Issei could only sigh.
However, as his dream continued, after the night with Ino, Karin, and Kaguya, he was brought to an empty space. In this space, Issei heard the voice of the system. It said [So you've finally made it to the absolute summit… Now I have no choice but to tell you the truth.]
"What?"
[Don't play dumb! This is what you've wanted since the start isn't it? To know why you were reborn and why you have me, the system.]
"Oh? Ok then, let's hear it. Why was I put in this position?"
[Well the truth is...]
The system's voice cut off, as Issei watched the empty space turn black and a titanic dragon appeared before him. This dragon was covered in red scales and had what looked to be green gems embedded in its chest, hands, elbow and knee joints, and shoulders.
The dragon said "Quite the strange dream, but since we're now partners, I guess it doesn't matter."
"Huh? Who are you?"
"You should already know… But since you're so talented, I guess I can tell you. I'm the soul of the Red Dragon Emperor, Ddraig. I see you've been hard at work developing your power. It's insane how you can already call me in your dreamspace..."
"Are you… attached to the Boosted Gear?" Issei could only think this "Red Dragon Emperor" had something to do with the new ability he received after reincarnating.
"You catch on quick, kid. How'd you guess that? Ever since you awoke your demonic powers I've been able to see that you haven't come into contact with anyone yet. There's no way terms like "Boosted Gear" are used by common humans..."
"It's a long story… Anyways, what do we do now?"
"We? Look kid, I'm just a tool at this point, so you can just use me to become respected and powerful in the underworld..." Ddraig was speaking so self deprecatingly, it was hard to listen.
"That sure is depressing to hear. Don't you want to do anything?" Issei would sooner or later have his god-like powers back, so he didn't want the spirit of one of his new skills to suffer; especially when the spirit was part of one of his newest "most absurd" skill.
"Kid, the only thing I want is for my host to beat the host of the rival, the White Dragon Emperor."
[New Mission Alert~
Mission: Defeat the host of Ddraig's rival Albion. Rewards: Albion's powers.]
"Deal! Now… how do I leave this place and wake up?"
"...Well usually, you would just wake up before we could do this introduction. However, your demonic magic can sustain our conversation for much longer than I expected… I guess you could try to summon me. That would cause my spirit to enter the Boosted Gear in your arm, which would probably end this dream."
"Mhmm? I haven't used the skill yet, so… how do I use it?"
"Just use your magic and called out "Boosted Gear.""
"Boosted Gear."
After Issei followed Ddraig's instructions, he felt his consciousness blur and the next thing he knew he was back on his bed. However, now his arm was covered in some sort of red draconic armor with a green jewel on top of his hand. Issei looked at the Boosted Gear in his hands and thought it was odd that he could feed it more will power; usually, that's a sign that the ability he was using was not at its optimal state.
Issei had grown used to not stressing his will, as even though it was strong enough to mess with Immortals, his current weak body could not handle too much of it. He would only dare to stress his will now, because the draconic gauntlet in his hands would accept his will without any backlash.
He used 1% of his complete will and the draconic armor extended to his shoulder. At 5% his entire chest, head, and arms were covered in red armor.
At 20% his entire body was covered in armor. This red armor also gave him a scorpion-like tail that was also covered in red draconic armor and… rocket boosters? However, Issei could feel that he was far from digging out all the power under his Boosted Gear.
[Host has unlocked a new form: Balance Breaker/Scale Mail Fusion Armor
Balance Breaker (Rank A | 0/100): Covers the user in draconic armor that self regenerates if damaged. While in this form, the user can ignore the ten second intervals to receive a boost, directly increasing the user's power to their limit. Amount of power gained, and time allotted in this form are determined by the user's physical and mental capacities. Current Effect: Increases power by 64 times for half a day, everyday.]
Chojusen kept rising the amount of willpower he used on the Boosted Gear until he reached about 80%, where the system told him to knock it off. Issei wanted to see what would happen if he kept at it, but the system told him that he would just be inviting death if he broke past something called a Juggernaut Drive Seal.
As the system explained, breaking past that seal would give Issei the full powers of the Red Heavenly Dragon Emperor. However, his will would be under the pressure of all the past hosts of the Boosted Gear. This would normally not be a problem for Issei, but he was already using most of his will just to reach the point before breaking the seal.
…
On the same day that Issei came into contact with Ddraig, he had an unpleasant encounter at night. After another day of school, Issei went on his now normal evening exercising routine. After he completed his thousand or so sets of common exercises, he started a run; he did all this while under twice normal gravity. He didn't want to get bored staring at the same scenery so he ran through different parts of the city.
On his 17th lap around the city, he found himself in the dead of the night alone in a park. This park was oddly familiar to Issei. Then it hit him. This was the park where he was forcefully reincarnated! As the realization hit him and he tried to remember who that red-haired woman who reincarnated him was, he was stuck by a spear of holy light.
The one who attacked him was definitely a high class enemy as Issei didn't even notice their existence until he had already been struck. Issei took the light spear that impaled him and pulled it out of his chest. Much to his dismay, he realized that this holy light was poisonous to him now that he was part devil; but his fiendgod bloodline helped him ignore the damage somewhat.
While his chest and hands burned from coming into contact with the holy spear, Issei used his Demonic Yang Rebirth to quickly heal himself. But the wound was a bit too serious to be healed with his currently low-level skill. Issei said "Who are you and why did you attack me?"
"Stupid boy, what other reason could there be aside from the fact that you're a stray devil! You don't have the mark of a master and none of your comrades are nearby, so don't pretend to be a fool! Besides Devils and Fallen Angels are natural enemies, only a dead devil is a good one." The fallen angel laughed menacingly, as he approached Issei slowly, while condensing another holy spear in his hands.
Issei wanted to fight back, but he had been caught off guard and his demonic magic had not yet reached the point where he could use two skills at once. Right now preserving his life was the most reasonable thing to do, but it would seem like it would be a pointless endeavor, as Issei was quickly losing consciousness and his wound wasn't even completely healed.
Before Issei was finished off by the fallen angel, a red magic circle appeared in front of him and that red-haired woman appeared as well. However, Issei was already unconscious so he didn't know how the events played out.
Beside the crimson-haired woman appeared a white-haired loli, a tall black-haired seductress, and a blond-haired pretty-boy. The girl with the crimson hair appeared to be the leader as she said "Don't even think about touching one of my servants!"
The fallen angel retreated before saying "Why, if it isn't the daughter of the Gremory Clan. I didn't know he was one of your little slaves. I hope you take better care of him in the future. After all, we wouldn't want him dying thanks to his master's lack of attention, now would we?"
"Thanks for the suggestion, I'll make sure to keep it in mind. Now, if you don't get out of my sight, I might just act on my rage and accidental end your little life. We wouldn't want that now would we?"
The fallen angel snorted at her comment and took his leave. He knew better than to mess with the daughter of one of the 72 Pillars of the Underworld. As he left, the red-haired woman carried Issei's body in her arms and dismissed those next to her. She personally carried him back to his home and started a "nice" recovery effort.