Sacred Gears created from the strong beings were fundamentally flawed. The first problem with them was that the host could not grow stronger than the being sealed in his Sacred Gear in most cases. The second was that, even when mastered, due to the nature of Sacred Gear, one cannot show the full power of the being sealed inside the Sacred Gear.
As soon as Rias finished the chant, she entered through her consciousness to the Issei's mindscape, where the soul of the Red Dragon Emperor Ddraig Y. Goch.
Rias looked at Ddraig nervously as she didn't know how the Red Dragon Emperor would react.
"What do you want here, young devil princess?"
Asked Ddraig in a majestic voice while he scrutinized Rias from head to toe. Even though the Longinus Boosted Gear was dormant inside its host, and Ddraig spent most of his time sleeping, he was very well aware of everything that took place in the life of his host.
He observed everything, so he knew what was going on and about everything about his host.
"I have come to negotiate with you."
Answered Rias as she looked at Red Dragon Emperor of Domination Ddraig Y Goch.
"Negotiate what daughter of Crimson Emperor?"
Asked Ddraig in a deep majestic voice as he stood up and looked at Rias with his draconic eyes shining. During past centuries, he was very well aware of the strength of the Chthonian Empire, as several of his hosts were killed by the Empire after either offending Nobles or creating conflicts.
His strongest host Belzard even met with the Crimson Emperor of the Chthonian Empire and was killed in a split of a second, even though he fought in Juggernaut Drive.
Only then did Ddraig realize that the Emperor of the Chthonian Empire had reached the level of Beings of Law.
"I came here representing my father to negotiate with you about the offer he made to you a century ago."
Answered Rias as Ddraig roared in rage as he took it as an insult.
She expected such a reaction, as Dragon Pride didn't know an end, but she had something prepared in her arsenal that would probably convince him in one go.
"Albion was revived long ago, and with help from the Empire, he will soon reach Elder Dragon Class."
She stated calmly, as Ddraig stopped in his tracks, frozen in one place, as he started at Rias with rage, thinking about that his rival had already got back his body, could freely fly through the sky and enjoy the pleasures of the physical body.
Not only that, but evidently, Albion was already nearing the Elder Dragon Class, which would mean that his rival would overcome him and leave him in the dust.
Just thinking about it made Ddraig grimace and frown in annoyance that his long-time rival would leave him behind.
Seeing that he was still not decided, Rias decided to push forward.
"Since Albion became a member of the Empire and was appointed as the Lord General of Imperialis Militarum, 6th Army Draco Aetherna, he had earned enormous amount of riches, gold, artifacts, treasures, and countless pretty dragonesses are lining up to him every day, and not only dragonesses but also beauties of other races. Additionally, he is already stronger than you thanks to assistance from Beings of Law of the Chthonian Empire."
After hearing that, Ddraig took an enormous hit, and it wasn't everything, as Rias continued shortly.
"You see that your host is a worthless pervert with zero amount of talent, who cannot awaken Boosted Gear even when he was reincarnated as Devil. And even if he did, what level would he reach with his personality? Probably Ultimate-Class could be considered an impossible achievement for someone like him. And then, with his personality and behavior, it is highly possible that mighty Red Dragon Emperor of Domination would become something along the lines of Breast Dragon Emperor or Oppai Dragon, such humiliation for mighty being as yourself is waiting behind the door."
Everything that Rias said continuously attacked all of the weakest points of Dragons. She instantly attacked his Dragon Pride, which took an enormous hit hearing that his rival was already more powerful and had everything that dragons were actively seeking: treasures, women, and gold.
And then, finally, she squashed the last amount of resistance he had by stating apparent facts about his current host and that he could be highly possibly renamed from Red Dragon Emperor of Domination to something humiliating as Oppai Dragon.
Ddraig was very well aware of what his host was like.
Dragons were naturally prideful, and the stronger they were, the more prideful they were, especially if they were titled dragons bearing some kind of title; they were incredibly proud of that fact, as not many dragons had a title.
After some time of silence, Rias could see that Ddraig's arrogance was broken down.
"So what do you propose, devil princess?"
Asked Ddraig.
"I am not princess, I was stripped of that title years ago for my own arrogance and weakness, but one day, I will get it back for my merits and power that I have achieved."
She corrected the Red Dragon Emperor as he looked at her curiously.
"Now, the Empire is proposing you the same thing as for Albion. You will get your physical body back and will be given an official position within the Empire, preferably in one of the Military Branches of the Chthonian Empire. Additionally, our Beings of Law will help you achieve the Elder Dragon Class. As Elder Crom Cruach has reached that level, he would be surely able to help you in that regard."
Presented Rias proposition of the Chthonian Empire for the Ddraig Y. Goch.
"I accept your offer."
In the end, Ddraig decided to accept the offer from the Empire, as it was beneficial for him.
"Excellent, now you only need to sign this."
Rias clapped her hands in happiness as she took out Soul-Geass and presented it to Ddraig.