Why he was a dragon.
Issei cannot fully grasp the reality that he has gone through at the moment that he believed it was just a dream. He just went with the flow of what he think might benefit him, never questioning why this all happened to him, it can be anyone else more capable than him, but it seems that luck favors him in so many unbelievable ways, or does it?
It was the meeting of the leaders of the three factions, where they talked about maintaining peace indefinitely, working towards a common goal of stopping a threat that can challenge even the powers of the great leaders Azazel, St. Michael, and the new demon king Sirzechs Lucifer, and since God is dead, everything is about to break into chaos, and to prevent that, the powerful leaders must make a truce in order to maintain peace and order. All breaks loose when a long forgotten faction has crashed the meeting, attacking the ones present, and even kidnapping Gasper, the vampire who can manipulate time and space, who is also under the responsibility of Rias Gremory, the sister of the devil king. After everything was settled, the white dragon emperor, Vali, attacked the red Devil emperor, Issei, and challenges him to a battle which no one can stop or interfere. Issei, who is more than a mile long away from Vali's power, was in the brink of defeat when suddenly, a burst of strong energy came out of nowhere, blasting Vali and shattering the barrier around the school. Everyone looked at the silhouette, and was shocked to see who released that enormous power that has easily blasted off the white dragon emperor like he was nothing. It was Issei's father, , who upon close inspection, also has a Longinus, Boosted Gear Armlet.
Mysterious person: My, my, are you really going to kill your playmate, kikuchi?
Vali: What? You … how did you know my human name? Wait, playmate? You don't mean … he's that kid? And you're … master?
Issei: Dad? Mom?
Rias: Father? Mother?
: yow, Issei, you must be wondering why I'm here or why is this happening. I and your mother are no ordinary human.
Issei: What?
: I was the former red dragon emperor before you. Don't worry Issei, we don't have any devil blood, but your mother is pure angel, that's why you are able to release your boosted gear even without proper training.
: My, My, you're exaggerating it too much. *Energy Barrier*
: Her wings, this aura, she's also one of the high ranking angels, the angel of Healing, Archangel Zerachiel!
Issei: Mom is a... Angel!? And dad is the former dragon emperor?
: yow, Ddraig, doing good there?
Ddraig: you sure are his father, you both are very perverted!
: seems like you're having fun, take care of him for me.
Ddraig: you know you can talk to me from your arm.
: I know, hahaha. Now, let's see how much you have improved, kikuchi, no, Vali Leviathan. My love, have you set up the barrier?
Mrs. Hyoudou: Yes dear, go amok! Issei, come to mama, I'll protect you. Rias, you too, get behind me.
activated his scale mail, it appears as a crimson red armor, with the crystals colors are aquamarine, and he also emits very large, monstrous aura around him, making everyone shocked and shaking in their feet, except for the leaders, who are amazed of the enormous power he is emitting. Hesitatingly, Vali chanted the words to activate his juggernaut drive, which he thinks will give him the advantage.
: my, my, you've become more powerful than I expected, don't disappoint me, kikuchi!
Vali: Shut up, I'll show you the real power of a true dragon emperor!
Shockwaves came from their clash, leaving large amount of debris around, shattering almost all the barriers set up by the student council, clashing faster than the speed of light. Shockingly, Vali Reverted back to his scale mail, looking very exhausted after launched a series of dragon shots from all of his fingers. Even though victorious, he was proud of the improvements Vali has made.
Issei: so that is the power of a true dragon emperor! Why didn't I know that my dad was like this? How was this even possible?
: You have improved more than before, kikuchi, but remember this, do not lose sight of what you are after, you can never be strong if something is holding you back, train more then come back to me.
Vali: I'm not done yet!
Suddenly, Bikou, the monkey king appeared.
Bikou: yow Vali, we're fighting the northern earth gods so I was ask to bring you back.
Vali: Issei, next time, I want to fight you, become stronger!
Issei: don't worry, next time I'll send you back to hell!
Then, they disappeared.
: Issei, you must have a lot of questions, I won't mind telling you everything, but when the time is right, you will know.
: My, my, Ken, go easy on Issei, I won't forgive you if something ever happens to him.
: now, I'll tell you everything, Issei ….