I do not own Persona 3 and Highschool DxD.

Prologue

April 9th (Full Moon)

I don't know why I am here in a green world, and devoid of live. Why, and when I got here? I panicked and don't know everything, heck I also forgot my name! And suddenly, some voice called me, and that voice managed to calm me a bit.

"Hey, are you alright?"

That voice... The owner of that voice is a male with a silver (or white?) hair, and some band-aid above his left-eye. He is wearing some red sweater vest, and a pair of black gloves. Yes, I remember him, he is a 'prince charming' of Gekkoukan High, Sanada Akihiko.

"Ye... Yeah, I think so...", I replied his question since it is impolite to not answer him. In a way, I am a bit thankful of him, because I am not alone in this place I managed to calm myself and recollect myself.

Now I remember, My name is Hyoudou Issei, 1st year in Gekkoukan High school. I go to that school partly because the girl in this school is cute, but there is another reason as well... And why I am here... Last thing I remember is I am going to Aohige Pharmacy to buy some cold medicine, and... Ugh, I can't remember...

"Good, you are alright... Can you stand?", He asked me while offering his hand to help me standing, and I graciously accept his help.

"...You are Sanada-senpai right? Where are we? Why there is no one else in this place?"

"...I can't answer you now, but If you can-", suddenly he stopped talking and turned his sight to his left. When I do the same as him, what I saw is something... I don't know if I can put my thought into word, but that thing is black and have many hand, it is something so bizzare, and please don't mention it's size...

"Damn! Why this shadow come out now!?', cursed Sanada-senpai. Shadow? What is He talking about?

"That's no other choice, let's go!", He then started to pull my hand, and running from this place.

"Wait Sanada-senpai! Please explain it to me what's going on!"

"There is no time to talking! Keep running unless you want to dead!", and that's make me shut my mouth.

Unfortunately, We must stopped our running because in front of us there is some black thing like before, but with a smaller size. Seeing that we cannot passed them, Sanada-senpai started to pull a gun from his waist. I think he will shoot that black thing with that gun, but what he is pointing with his gun is not that black thing, he is pointing that gun to his head instead.

"Hey, what are you-", my attempt to stopped him is halted because...

"POLYDEUCES!"

After Sanada-senpai shot his head with that gun, something appeared with some surge of energy. That thing have long blonde hair, with some big needle at it's right hand. That thing also don't have a proportional body, it's hand and leg is too small for his bulky body. But it's power is amazing despite it's weird appearence. That thing can summon a jolt of electricity to completely destroy it's enemy. Unfortunately, because we had to stopped our running for fighting a bunch of small 'shadow' thing, that big 'shadow' thing managed to catch us.

"Damn, it can't be helped! Hey you, get away from this place!"

Get away? to where? A part of me want to get away, but I also scared to move from this place alone. Besides, I also cannot leave this guy alone, even though he can defend himself.

"GUAAAAAAHHHHHH!"

Apparently when I got lost in my thought, Sanada-senpai got attacked by a big blast of fire and thrown to the lamp post, hurting his left hand. And when he got blasted by that big thing, his gun thrown to near of my leg. Absentmindedly, I picked that gun.

"Hey, it is not a real gun! Why you are not running!?", I cannot hear what Sanada-senpai said, my vision got focused on that gun. I recall what senpai doing before, and I pointing that gun to my head. Somehow that black thing stopped it's attacked, maybe it want to see what I could do but honestly I don't care.

I hesitated. What if this gun is real and instead of helping me, this gun will kill me? Not to mention what if I cannot call something like senpai? Either way it is do or die. Oh, I also thinking maybe this is dream, and by pulling this trigger I can wake up in my bed. Unlikely, but the chance is not 0%, so...

"RRRRRRRRRRGGGGGGGGGGGGGAAAAAAAAAAAHHHHHHH!"

BANG!

I pulled the trigger.

Black. I can only see black in here. Am I dead? Is that gun really killed me? When I am thinking that I am dead, immediately a massive fire entered my vision, and a huge red dragon appeared to me.

"Well well, it is a surprise indeed... Instead of using your Sacred Gear, you managed to find a way to temporary unseal me from your soul... This is a first time since God sealed me into Sacred Gear..."

Who are you?

"My name? You are a lot calmer than I thought... Usually when my host seeing me for a first time they would feel fear... Ah, maybe that black thing is more scary than me?"

As I said, Who are you? I admit that black thing is scary, but If it make you any better, you are also quite scary to me.

"Hahaha! So you think I am scary as well? Well, looks like human fear of dragon is still exist... Oh well, my name huh... I am Sekiryuutei, a Heavenly Dragon that resides in your soul, more accurately in your left arm!"

Great, today is not my lucky day. After I somehow got into a green place, I got chased by a huge black thing, nearly dead, and now I learned that I hosted a big red dragon in my body. If he revealed it to me when I am not in this situation, I would be panicked and think I am crazy.

"By the Way, I would ask you... Do you want to live?"

What are you asking now? Of course I want to live! If I want to dead, I would not pulled that gun trigger!

"I see... Then, I have a proposal..."

A proposal?

"Yes, I will help you to get out of this situation, in exchange of release me from this prison. I don't mind if it is only temporary."

Release you? Wait you did mention I found a way to release you temporary.

"That gun can provides someone with a potential some stimuli to summon his/her inner strength from his/her sea of soul. I don't know how it's worked, but apparently these gun can summon me albeit temporary because I got prisoned in your sea of soul."

I don't understand anything you said, O' Mighty Dragon.

"Hmmph, like I said I also don't understand how it's work."

Then don't talk at all, you only make me confused!

"Hmmph. So do you accept?"

It's not like I have a choice, right? But I have to remind you that these gun is not mine, so maybe after this I cannot release you anymore.

"Hmmph, I am aware of that. Now, let's go partner!"

When I opened my eyes, I returned to this green world. However, I noticed that Sekiryuutei is above me, flying in his glory. Then he said this.

"I am thou, and thou art I. From thou prison of thy soul I hath released. I am Ddraig, A Red Emperor Dragon."

Author Notes :

Well, I am not planning to makes this story, but this idea cannot go away from my head. This idea appeared because I am reading some DxD and P3 crossover. There is always MC from P3/P3P/P4 come to DxD world, but there is no DxD character comes to P3/P3P/P4 world. Because of that this idea cannot leave my head.

Mind you I probably not updating this story often (not when my other story is a bit stuck), so I will gladly accept it if someone want to adopt this story (just make sure you mention my ID in your story and PM me so I can follow your story), but if there is no one want to adopt this story, I will try to finish this (just don't get your hopes up for a fast update).

The basic of this story is :

- Issei not replacing Makoto / Minato / Minako.

- Issei is not a Wild Card, but his real arcana is a Fool, although He appeared as a Magician arcana when he is in SEES.

- Ddraig is not a persona, he is just a Dragon that had been sealed into Issei, and somehow can be summoned by evoker.

- Ddraig is Overpowered. What can you expect? He can killed a God! Heck, He is a third being strongest in the world, only lose to Great Red and Ophis, and got tied with Albion.

- To make up for his Overpower 'Persona', Issei has the worst stamina among his friend. Just summoning Ddraig 2-3 times is enough to make him tired, and in tartarus a 'tired' status is very bad. Of course his stamina will get better later.

- Issei can used 1 Handed sword and Fist (His normal attack can be slash and strike).

- This story will not includes Social Link, but Issei can be Makoto/Minato Magician Social Link or maybe his interaction with Makoto/Minato will not grant Makoto/Minato Social Link (like his interaction with Junpei), who knows? This story is in Issei PoV anyway.

- Issei has potential to awaken his real persona, but He only managed to summon it later before facing Nyx.

Ddraig statistic as a Persona :

Ddraig

Magician Arcana

Null Fire, Strong Light and Dark, Weak Ice

Lv 99 (Issei is only level 1, just for your information)

Str, Ma, End, Ag, Luk all 99

Moveset :

Boost (Double Issei parameter, basically like Heat Riser, but can be stacked and can only for himself)

Agidyne

Maragidyne

Akasha Art

Megidolaon

Dragon Shot (Heavy almighty attack to 1 enemy)

God Hand

Fire Amp

Now you see why I said Ddraig is Overpower?

Anyway, please tell me what you think of this idea.

Chichiryuutei, out!