Dragons... demons...they are all mythical monsters... well so we were told. Now our fav dragon slayer will be meeting them very very soon.

-Firoe, Tartarus War-

"Fire Dragon Brilliant Flame" In a burnt down area a massive crater suddenly appeared, making a big explosion and also sending quite a strong shock wave destroying a large amount of trees. The one at fault was no other than the, tanned, muscular, spiky pink haired dragon slayer, Natsu Dragneel.

While Natsu was finishing of Mard Geer, Master of the dark guild, Tartaros, he could sense something was off, so he started to turn around to see how the battle between Igneel and Acnologia was going.

He felt his heart drop when he saw his foster father Igneel fall to the ground as he began to run towards his father he noticed acnologia was readying a dragon roar, while he was running towards his father he heard a voice in his head...

"Natsu, I am going to die soon, my arm has been ripped off, also I'm nearly out of magic...

"I know you have something hidden in you and I would like you to release it all.

"Being with you Natsu have been the happiest days of my life it's a shame they're going to be cut short...

"I love you Natsu, also remember to give me many grandkids." The nearly dead dragon said as he coughed out blood letting out a chuckle.

"Igneel you can't die, you stull have much to tell me." Tears escaped his eyes as he saw his foster father being killed in front of him.

"Igneel!..."

The dragon king now started to let of a roar while flying off.

"It's time..."

"Unleash the beast!"

The ground began to crack, the sky started to turn red, and Natsu definitely wanted to bathe in the Dragon King's blood.

As the dragon tried to fly away he noticed a breath taking magical power, it turned around to see a monster look right in his face.

Letting out a scream, the dragon king tried to fly away. But failed immensely when realized Natsu had ripped of it's wings.

Letting out a roar, a transformed Natsu was laughing his head off with a scary look on his face.

Crashing to the ground acnologia said something he shouldn't:

"I'm going to kill you just like I did your father!"

This obviously angered the young dragon slayer so he readied another attack to the Dragon king, acnologia.

"A.N.D, ABOLOSHING. NAPALM. DISCHARGE."

(Did you like how I did that? In his E.N.D form most of his attacks are going to be like that.)

A some sort of flames appeared over acnologia, now these were not just normal flames, these were napalm flames which means there is no way to put these flames out since napalm is a extremely flammable liquid used in warfare.

'I have to redirect this attack or it will kill me' Acnologia thought aloud.

Using a breathe attack, acnologia sent the attack into the sky, making multiple universal cracks.

(Since this is a crossover you guys probably know what's gonna happen.)

Annoyed because he couldn't kill the guy that killed his father, unleashed another attack.

"D.I.E. DEATHLY. INTERSTICE. ERUPTION." A Bunch of crimson bladed weapons emerged from the lava covered ground, Erza's Re-equip magic look absolute rubbish comparer to this

"ARGGGGGGGGHHHH!"

"YOU BASTARD!"

It covered the dragon king head to toe no part of it's body was left unturned too. Knowing this wouldn't kill it so easily he summoned a flame as he approached the Dragon King.

"DEATH FLAME"

"Nooo what are you doing, get away you monster!"

"Hahaha." A demonic yet crazy laugh escaped the demons mouth as he walked closer to the dragon.

As you know, the Dragon King has many open wounds and is very weak so there is no way he could possibly escape.

~NATSU'S POV~

I hesitated I didn't want to do it because it's not what fairy tail does, we don't kill! Yet, I'm still so blood hungry.

"What do you mean?"

"He killed your father!"

"Let me take control! Stop denying me!"

Ahhrrrrghhhhh!

-FAIRY TAIL-

"Has anyone seen Natsu!" happy screamed.

"Him and Igneel are fighting acnologia right now." Gray said as he started to get up.

"Why isn't anyone helping!?" Replied happy.

"Do I look like a dragon slayer to you?"

"Also, all the dragon slayers are getting treated right now?"

"Fuck you gray!" Happy shouted as he surprised a large amount of fairy tail.

"I'm going to look for Natsu and the girls."

-HAPPY & THE GIRLS-

"Happy what are you doing here?" Erza shouted.

"I think Natsu is in trouble." Happy cried alarming all the girls.

"Where is he?" They shouted in union.

"He's outside fighting acnologia!"

"Everyone get up, were done resting!"

'I hope he's alright, Erza, Mira, Lucy, Cana, Juvia, Wendy thought.

~WITH NATSU~

"I told you to stop resisting" The inner Natsu said.

"I don't want to kill it."

"No matter what it has done"

"Natsu what's going on?" Erza and the rest said.

"Girls, what are you doing here?"

"What happened to..."

"If you do not listen, you must be punished, now that I've took the life of your mates you must listen to me now!" The inner Natsu said as 6 crimson spears pierced the chests of his mates.

"Natsu why..." They said as they dropped dead.

"MEMORY CHANGE: ACNOLOGIA KILLED YOUR MATES, KILL HIM NOW!"

"ACNOLOGGGIAAAAAA" Natsu screamed as he released a roar.

"G.O.D, GREAT. OBLIVION. DESTROYER." Natsu screamed.

It was pure destruction, black, crimson spikes coming out the ground, gutting the dragon king, making him let out a scream.

"Ahhhhhhhrrrrghhh"

"Don't worry you cant die yet, I'm going to absorb you and Igneel over there." E.N.D said.

"It seems like we've made a universal crack." E.N.D said.

"I guess you'll be seeing these two Dragneel a lot more." E.N.D said.

"What do you mean?" Acnologia said.

"While he's asleep, he's going to absorb you and his dad, Igneel."

"He did it with his weakling friend, Laxus, he had no magic left so he absorbed his lightning."

(E.N.D IS NATSU BUT HE HAS SO MUCH GREED AND HATRED IN HIS HEART IT KINDA CREATED ANOTHER PERSONALITY. I'LL OFFICALLY MERGE THEM LATER IN THE STORY.)

"Don't worry your not going to die, your just going to live inside him for an eternity." E.N.D said nonchalantly.

"What!"

"I got stuff to do!"

"Like what? You're a genderless Dragon King..."

"Also I remember you tried to mate with me."

"That was centuries ago." The embarrassed dragon said.

"Yeah, yeah."

"While your inside him, do not say a word." The demon demanded.

"No fighting with Igneel either." The demon demanded.

"BTW you're not stronger than Igneel, he would destroy if he had his human body." E.N.D said as he stuck his tongue out.

"Stop bullying me." Acnologia wiped his tears.

"Well that portal is universal crack is going to sweep us up, now I will proceed to go back into human form." E.N.D said as he deactivated the E.N.D form.

"Where do you think its going to take us?"

"The DXD universe..." Mumbled E.N.D

"Hmmm, interesting." laughed Acnologia.

"What about your mates?" Acnologia asked curiously.

"You did that remember, hehe." He chuckled.

"Fuck you..."

...

"Where am I?" Natsu screamed.

"Your in my void young one."

"Who are you?" He got in a fighting stance because he was afraid of who was there.

"I am the Holy Black Dragon Emperor, Vediga."

"A dragon?"

"Yes, also you were immensely injured so I healed you.

"Thank you, I'll be on my way back to magnolia now.

"Believe me or not but we're in a whole other universe..

"What!"

"I'm done for."

"I can send you back but..."

"Hell no, send me back right now!"

"I'll send you back if you become my host."

"What's a host?"

-10 MINS LATER-

"So what's a host again?" The pink demon said as he scratched his head.

"Don't worry about that." He said as a vain popped on his head.

"Let me rephrase this, I can give you my power."

"How about that?"

"Hmmm ok, sure."

"I need power, I saw my dad get killed right in front of me and I couldn't do anything." Natsu said as he started to sulk.

(Natsu is not aware of what happened when he was fighting acnologia, E.N.D. wiped his memories.)

"Also, people say I'm dumb, is there anything you can do about my intedegence?"

"Don't you mean intelligence?" The black dragon cringed.

"Yes, that's what I said."

"Nevermind"

"So how do I get this power up?"

"And why can't I see you?"

"Oh, sorry about that." The dragon said as he appeared out of nowhere.

"In the name of Mavis..."

"You're fucking huge, bigger that Igneel and acnologia combined."

"Hehe, the way for you to get my power is to drink my blood."

"Is that all?"

"That's pretty easy I guess."

"Also you're pretty strong and I sense two I've souls in you, do you have any sacred gears?"

"What are those?"

"Never mind, now repeat what I'm saying."

'Hmmm, it seems like he's not aware of these two powerful souls that are in his body'

"Ok"

I am here by the the host of Vediga, The emperor of Holy Black Dragons.

"I am here by the the host of Vediga, The emperor of Holy Black Dragons."

"Good, now drink my blood, child.

"Arrrghhhhhh" Said Natsu as he fell into the void.

"Your taking it pretty well, haha."

"Well I am a dragon slayer."

"A dragon what?"

"I am a dragon slayer, I have the power to slay a dragon."

"I also have the same attributes as a dragon, I can use their respected element on any part of my body, I have scales, well I get them when I'm mad or absorb a massive amount of magic."

"My father was the Fire Dragon King, Igneel."

"So if you and me got into a fight who would win?"

"Hmmmm, I don't know."

'I don't think he's being cocky about that, he has the potential to even kill the demon 666, luckily I found him first and not that wicked vanishing dragon.' Thought the Dragon Emperor.

"Well that's ironic..."

"I'm going to send you to the human world, earth, maybe you might run into some devils, angels, and fallen angels."

"Okay by..."

"Ahhhhhh, why so quick, I'm gonna die." Natsu said as he was falling from the sky."

-GREMORY CASTLE-

"Today is so boring, I wish something interesting would happen" a young man in his early 20's with blue eyes, crimson hair, and a muscular build, said as he looked out his office window.

BOOOOOOOM!

"What the..."

A massive meteor was seen crashing into the gremory's garden, creating a shockwave and destroying anything that was near it.

"Rias, Mother, Father! Is everyone alright?" The now identified, sirzechs said completely forgetting about his wife, Rosetta.

(Grayfia is not going to be his wife in this story)

"Yes we are, anyone know what the cause of that bang was?" A crimson hair female with blue eyes, pale skin, and a very large bust and black dress.

"It was a meteor, it landed in our garden, go get grayfia, we need to check this out."

"Yes, brother." The now identified Rias Gremory answered.

-10 MINUTES LATER, IN THE GARDEN-

"Grayfia, your ice would be nice right about now." The crimson haired Satan said with a smile.

"Yes master." Said a beautiful women appearing to be in her early twenties, she also has a long silver hair and bright silver eyes, she is seen wearing a French maid outfit with a white maid headband, and has bright red lips.

Putting out the flames then appeared our favourite dragon slayer, Natsu Dragneel.

"It's a boy?" Rias said with a blush.

"Yes, a very attractive one at that." Grayfia said, checking out the pink haired dragon slayer, then got stares from the gremory family which she ignored.

"Am I the only one that has noticed he's not injured at all even though he took guide the fall." Sirzechs said with a laugh as he began to sense immense power radiating from the boy.

"Do you feel that power grayfia? He's even stronger than you!" stated the crimson haired Satan.

"What?! I thought grayfia was the strongest?"

"Not anymore, now let's bring him in." Sirzechs said as he put the boy over his shoulder.

"In the name of Satan...

"He's heavy as fuck."

"Language! You got little rias around." Grayfia said with a glare.

-NATSU'S DREAM-

"I don't want to kill him, leave me alone!" Natsu shouted

"How dare you disobey me!?"

"I'm the one who's saved you all these times, without me you would be dead."

"Killing is not what fairy tail does and I'm a fairy tail member!"

"Haha, you actually think they care about the rules, or even about you for that matter?"

"They're leaving you for dead out here."

"No, they are just resting!"

"Natsu there you are" Voices from a far said.

"Girls! What are you doing here!?"

"What happened to..."

"If you do not listen, you must be punished."

The inner NATSU spoke out as he took control and impaled the girls with crimson and black spears.

"We loved you Natsu, why would you do that to us..." Juvia and Lucy cried out.

"You betrayed us." Mira, Erza, Cana cried out.

-WITH NATSU-

"Nooooo!"

"Your finally awake." A crimson haired beauty said as she ate an apple.

"Who are you..."

"Now that's not anyway to talk to you saviour." The cheeky red haired said.