Issei finish recruiting Azi Dahaka who had been told a place where he can let loose fighting powerful creatures. He told about the training facility where can fight any opponent replicated in the place. Any below middle primordial gods can be replicate inside the training grounds without fear of it being destroyed.
He had worked tirelessly to create the perfect place to train which why it durable enough for the heavenly dragon to all-out battle. This is the same place where Issei trained his [Ayin] spear.
Now that he was alone in the sub-dimension began to revive another evil dragon and what appeared was a black mist that encompasses one hundred meter of land. From the most glowed three silver peering through the mist.
"Fascinating. Someone bold enough to revive from my eternal rest."
The creature gradually form into a solid mass revealing the appearance of a black Eastern Dragon exceeding one hundred meters in length. It had gems along his body, all of which released a shimmering, silvery glow.
It had three eyes upon his head which released the same silvery glow as his gems. Issei could feel a similar ominous aura as Azi Dahaka however it more akin to the eerie silent of the night.
"I sense someone I know. Is it azi dahaka? His aura reek of this place. Humph are you the fool that was bold enough to revive me??"
"I am that fool and my name is Issei Hyoudou. I'll get straight to the point why I revived you. Submit to me or die."
"Tsk I hate people that is straightforward. Are you telling me to be your mate?? You don't have the qualification."
"Wait wha-"
Issei couldn't finish his sentences as mass of darkness began to attack him from all direction. He evaded all of them then summon destruction needles to countered the onslaught darkness.
He swiftly leap through the air then did triple front flip afterwards slammed his feet into Apophis's enormous head. The force resulted in the massive crater with a small ravine being created. A cloud smoke enveloped the entire area while Issei stood on top of the enormous snake.
"I think you're misunderstanding! I meant to become my subordinate!!"
Issei explained and didn't expect that Apophis was a female since he hadn't been informing in the past when they fought each other. Apophis remain silent for a moment then surround Issei with a shadow spike trying to pierce him but he was able to easily evade.
"Is that so? Well, I don't care if it's being mate or subordinate because I will not yield to someone weaker than me!"
Apophis summon a large quantity of dark water that dissolving the land turning it into a barren wasteland. A stream of water shoot towards Issei in unbelievable speed but he evade every single one while approaching Apophis then held out his hands.
A power blast of holy lighting was shot point-blank to Apophis who felt the agonizing pain coursing through her body. She didn't expect that the person had holy lightning that is her weakness being an evil dragon.
"Fufufu you might be more a challenge than I expected! If I have to guess that Azi Dahaka had already fought you?"
"Yes, he easily lost to me the same as you soon."
"We will soon see!"
Apophis began to reform her body into smaller features. What appeared what a woman dress in high neck dark coat and golden streastreamlines an overcoat and feathers on her shoulder. She had short her with one side being longer and intently stared at Issei looking down on him.
"This is much better than my true form."
"Not bad you look good."
"F-Flattery won't give you much advantage."
Apophis blush from his straightforward reaction but calmed herself as she began summoning countless dark shadow blasting barrage of shadow bullets towards Issei who did the same but with a Destruction needle.
Both were equally matched but Issei reappeared in front of Apophis who anticipated the attack. She was able to redirect Issei first then held her palm to attack with her shadow but Issei was fast enough to slap her arms to the side to take another strike yet Apophis flip downwards then back kick Issei straight to his face.
However, Issei saw this and lean back wrapped his legs into her waist then slammed her body through with immense force. Apophis remained conscious due to her thick magic barrier quickly knee strike Issei face enabling Apophis to escaped then flew to sky blasting barrage of dark flames that burst the surrounding trees.
The sheer power of the flames had the size of a small mountain incinerating the whole place. Apophis only saw smoke but remain wary sensing still alive inside the flames.
"Hey, I know you're still alive! Don't tell me that this is all you got huh?"
"Of course not."
Before she could react Issei appeared behind her and felt impending doom coming instantly tried to evade but everything became a blur and she was a hundred kilometers away from where she was.
'What the fuck is that!? Dammit, it was too fast for me to react!! Is this his full power?'
"Unfortunately it is not."
Issei reappeared with a crimson gauntlet that was constantly boosting his power for that split second. He didn't anticipate for Apophis to burn his body despite his durability. Therefore, he decided to used the boosted gear even though he can just boost himself without the gauntlet still prefer it to appear.
It became second nature to him and had a hard time getting used to it. Issei had changed its appearance into a much less bulky form. It still retains its crimson color but had golden streamlines and smaller green orbs.
"Hahahaha I didn't expect that you're one of the heavenly dragons! This is truly interesting way to be greeted after being dead for so long!"
"Are you still planning in fighting me?"
"No, I concede. You seem to be capable mate for me."
"Uhmm no I only need a subordinate and not mate."
"Don't make me laugh you reek of lust and sex."
"Have it your way. Just follow this simple rule…"
Issei began explaining everything to her the same as Azi Dahaka and agreed to it without problem but she quite impressed from his determination to protect her mate and instantly become in rage if they are threatened like a true dragon.
"You are quite the interesting man, Issei Hyoudou."
"Well come with me since it would be unfair for you to stay in place. Don't worry I preferred your place to live in."
_______________________________
The next day, the evil dragon had settled in their place to lived in which was a sub-dimension created by Issei. His lover meat with then comment about them being a range but explained about the seal place on them.
He was currently laying on Rias lap on the couch accompanied by Yuumi, Koneko and Kuroka. As the rest had their own free time and worked to do.
"I see they will be useful and be better to be ours than the enemy. However, you need to be careful since we don't if they'll try to act carelessly."(Rias)
"I know don't worry too much."
"You're one to talk."(Rias)
Issei warily smiled since his the one who kept worrying about them despite having power of a S-ranked Ultimate class. Though, he was happy that his lover worry about him even if only few can fight him and none can survive.
"I heard from Irene that they tried to fight you?"(Yuumi)
"Yeah though they didn't stand a chances like in the past."
"I heard Vali-chan is fighting both of them nyah."(Kuroka)
"The snake kept trying to seduce Ise."(Koneko)
"Oh my is little Koneko-chan jealous?"
Koneko blush and kept eating her cookie that Issei specially made for and no one else can get. Kuroka hugged her little sister who pouted.
"Ah, shine is so cute when she pouts Nya~"
"Master there are people that would like to meet you."
"Oh there here huh? I expected them to visit at night."
Issei stood up strength his body showing his well define muscle. He was wearing a skintight high neck sleeveless shirt.
"Let's go meet up with them."
Rias and the rest followed Issei where the Automata maid had Irina and Xenovia to the Guest room. They Saw Issei wary seeing the other devil with him.
"I-Issei is that really you?"