***
No one's POV

     Aizen was quick to recover from the initial shock of the Celestial King's appearance, he was soon back to his arrogant self.

"At first I changed my mind about summoning you, but this will do as well," He spoke to the King rudely, crossing his arms. " I demand your loyalty and allegiance."

  Everyone stayed silent. The Celestial King just looked down to the man, to him Aizen resembled a small cockroach worthy of stepping on.

"Well?" Aizen said crossly. "Why else would you be here? I summoned you and harnessed the power of the Celestial realm. You have to bless me with your title."

  Natsu couldn't help it anymore and fell on the floor laughing, to the point of humorous tears. I can't believe I was seriously fighting this guy a second ago! He's a fucking child!

Aizen shot Natsu a hateful glare but that didn't shut him up.

"I'm just here to lend a hand to an old friend." The Celestial Spirit replied simply, referring the blonde mage that was currently unconscious alongside Yukino.

"Thanks stache-man!" Natsu grinned, waving to the big burly man with the very stylish moustache.

Aizen was shocked by the remark and looked in between the two of them. "S-stache-man??"

"Well now that I've got some backup I'm all fired up!" The  Fire dragon slayer exclaimed, pumping his fists together in determination.

"Indeed."

"Wh—" Aizen began to look furious. "I had a feeling things would backfire!" He raised his hands. "I'll just have to defeat both of you!"

***

    Erza and Gray could hear the commotion near them, yelling, most prevalently, yet everything they heard was muffled.

"Here." The scarlet haired mage exclaimed pointing at a large door, the size of the entire wall. "Let's try to get in and give our assistance."

"Yeah."

  She reaches the door handles and figures they're locked. Shaking on it violently, nothing happens. "It's locked. There must be some force behind this door keeping whoever's in, in and whoever's out, out."

"Lets just hope Natsu made it in time."

Gray opens his fists to create a battering made out of ice. Erza steps out of the way and helps him carry the large object. They nod and swing the ram full force into the wooden door, shattering the material into little splinters.

Their moment of victory is cut short. "Shit."

"There's so much destruction..." Erza muses, seeing what's blocking their path.

"It'll be impossible to get through all this rubble. Even if we could, we don't know if it'll cause the building's structure to go weak. This is the source of the tremors after all.." Gray observes and sighs. "Natsu will just have to do this on his own."

***

"You, human are indeed humorous," The Celestial King replies to Aizen, despite the heavy politeness and formality in his voice, it was clear that was snarky insult. "I'd like to see you try."

"My clairvoyance has helped me understand the situation." The King booms, his voice getting angrier, the giant decked in armour seemed to frighten Aizen the more he talked. "Not only have you hurt my dear friend, Lucy, but you have also broken the ethical laws of the Celestial realm."

   He holds out his hand to his side and in no time an overbearing sword appears in his hand, the weapon was five times the size of both Natsu and Aizen, who surprisingly still stood his ground. "I'll reprimand you."

"Yeah!" The pink dragon slayer dragon slayer joined in. "You'll pay everything!" He lit his fists ablaze. Not just for Lucy, not just for Luke, but the entirely of the celestial spirit realm!

  The Spirit King and Natsu nod to each other, both on opposite ends of the Serpent's Wing member who seemed to be losing his temper.

"Fools!" His open palms shook with magic, Aizen now being able to replicate the King's technique, summing a smaller scale sword of his own.

  Luke was watching the scene unfold, unsure of the situation. That giant man had frightened him at first, but was told by the exceed who lied next to him that the "old stache man" was on their side.

The blond then skipped over to Aizen himself, not daring to glance at the unconscious bodies of his mother and her friend. Aizen to Luke seemed to be unhinged, he was able to feel the raw power radiating off his body—it almost seemed like to much.

  Can this mans body even handle the power of a King? That scary-looking dude? I hope not. His eyes lastly shift to his father, a look of pure determination plastered on his face which somehow filled the young boy with warmth and hope. Do they notice the bad guy's weird behaviour?

Aizen gave off some weird battle cry as he charged at the Spirit King, his sword emitting a bright glow. "Celestial striker!" He chanted as the sword attempted to dent the King's armour. The attempt was futile as when the dust cleared, he was shown to be floating midair.

"Tch, you think you're so clever, huh?" The villain's eyebrows furrowed. "You forget! I absorb your abilities as well!" Soon Aizen's feet had left the ground as well, his body being able to lift to the King's level for an easier battle.

"Happy!"' Natsu shouted for his blue companion.

"Aye!"

He was lifted off the ground by the exceed's angelic wings—Happy was almost at his limit, sure, but it would be terrible timing to give in to retrains now.

"Fire Dragon's: crushing fang!" The dragon slayer lurched at his target, clawing at him with his flamed hand. He was only able to tear the fabric from Aizen's coat.

He's still too strong for me—if not stronger. Natsu could feel the extensive power off this guy. Opening the gate seemed to have some negative effects. Aizen's viens were glowing a gold colour underneath his skin, and his breathing was heavier.

"Lend me your strength!"

The Spirit King nods and Natsu could feel a surge of strength and resilience enter his body, with the Celestial Spirit King by his side he stood more of a chance.

  Aizen spun to the salmon haired mage, raising his sword and almost knocking him to the ground, Happy was able to narrowly dodge.

With the granted strength from the celestial spirit, Natsu felt he could step it up a notch. His energy danced around him, and he opened his eyes in anger. "Dragon Slayer's secret art; Crimson Lotus: Fire Dragon's fist!"

  Natsu began rapidly punching Aizen, landing each blow. Explosions hung in the air as the Dark Mage was flown back, blood spilling from his mouth.

Alright, I was finally able to get him!

"You'll pay for that!" Aizen yells. The successful attack seemed to have but the already unstable man on the edge. His once colourless and dull eyes shone yellow, his pupils gone.

"Did he just grow in size?!" Natsu shouts in absolute shock, the guy before him had grown! Not as large as the King himself, but larger than a regular human.

"It seems the gate is strongly effected him," The Celestial Spirit King exclaims. "With the rate he's going, my magic will either accept him or he'll be rejected."

"R-rejected?" Happy gulps. "What's that mean?"

"It means we'll win this fight."

"So what you're saying if I piss him off enough to overcharge he'll become normal again?"

  The King nods. "That is correct. The power will leave his body. The absence will almost kill him. If the magic accepts him than he'll be near unstoppable."

As if he wasn't like that before.. Natsu passively thinks to himself while putting his fists together. Time to show him what I can do!

"Celestial King's; exploding blade!" Aizen appears, recovered from Natsu's last attack. The dragon slayer is hit in the gut with the magic-enhanced sword and he harshly drops to the ground .

He wipes the blood on his chin with his arm, ready to pounce back up.

"N-Natsu..." He looks over to see Happy on the ground with him, looking frail and week. "I'm out of magic power. I'm sorry."

"It's okay, bud," Natsu smiles at him reassuringly. "I don't need to fly to beat his ass."

He turns to Aizen who was still airborne, despite the distance Natsu could still see those damn creepy glowing eyes of his in detail. "Don't think this is over yet!"

"Dragon Slayer's secret art; Crimson Lotus: Exploding flame blade!" With a swipe or his arm Natsu created a torrent of flames, heading towards Aizen. The attack hits and he himself his flung, into a wall, creating a massive creator and shaking the floors.

    Wow, my dad is that strong! Luke thought to himself. He decided to make his way over to his mom, who began stirring.

"L-Luke?" She brought her head off the ground. "What's going on?"

"It's okay mom!" Luke smiles, telling her to save her strength. "Natsu and the giant man are fighting the bad guy!"

The blonde looks over to see Aizen and Natsu in an intense battle, Aizen looking the most erratic he's ever been. Natsu with his vest torn and abs exposed. Not the time to be thinking about that.

"Don't worry, my friend." A voice suddenly enters her head. "Natsu will be alright. I have lended him my strength. This shall be over soon."

Lucy smiles at the King's reassuring and kind words he had told her through telepathy. "Thank you."

    Natsu was now much closer to the ruffed up Aizen, who had fallen from the wall to the ground.

"I'll make you regret ever involving Luce and her son into this!" Natsu yells, his hand still on fire as he made his way towards the Dark Wizard. "You should've never messed with Fairy tail!"

"To think the Celestial King would help Fairy scum like you," Aizen composes himself and brings his sword to his side. "Truly pathetic."

"What's pathetic is your need for power," Natsu stands his ground, ready to punch the guy once more if he had to. "Erza told me all about your past, being born magic-less."

"Tch, what'd you know?"

"I know it's wrong to steal from others. And that you don't need magic to be content in life! All you need is family!" At this point, due to the King's strength lending its own to Natsu, his usual fiery-aura had a starry tint to it. He was getting hyped to land the last blow on Aizen.

Family. Lucy watches the scene unfold, almost unable to hear their conversation take place. I took that from him. Guilt washes over her, she almost loses consciousness once again. Sure he has Fairytail, but true blood family, It's my fault he couldn't experience that.

"Mom?" Her soon looked over at her concerned, his onyx eyes almost made Lucy wanna cry at the close resemblance.

Maybe she deserved for this unhappy ending. She did this to herself, never coming back to Fairytail was foolish. Like Aizen, Lucy thought she could handle herself alone. Now she knows how truly wrong she was. She needed Fairytail. She needed Natsu.

"I'm alright." She exasperatedly sighed. "I'm just tired."

"I don't need family," Aizen harshly replies, raising his sword to point at Natsu. "All they ever did was look down on me. Never aloud, but I could tell. I could tell they were disappointed in their weak son."

Aizen lunges at Natsu. "All I need is power!"

"Then I won't feel bad about this!"

Natsu lunges as well, with the help of the Spirit King, he moves faster. "Fire Dragon's: brilliant flame!" His hands ignite and forms a large fireball that engulfs the mage. That should piss him off.

"You thought that could defeat me?" Aizen stands up from the blow, smoke blowing around him, he had obvious first degree burns, but nothing serious.

"It didn't need to."

Aizen clenches his fists, ready to direct more of his newly
acquired power. "Wh—" he looks down at his fists. They were numb was more magic than intended bursted through them, a painful sensation formed in his head and chest. "What's going on...?!"

"It seems you can't handle the responsibility that comes with great power." The Spirit King answers, coming forth from the sidelines of the battle.

"B-but I opened the gate! I was able to take your power! I'm worthy!" He clutched his head as more and more unstable energy surrounded him, it felt as if his eyes were going to explode any second.

"You are worthy of nothing." With that the Spirit King decided to land the finalizing blow. Raising his enormous great sword for the first time.

"Meteor blade." He placed two hands on the weapon's large hilt, executing a slashing movement, causing a linear blast to eject and hit Aizen full-force, the impact breaking the side room instantly.
Light poured through the cracks, it had hit the wall exposed to the outside, therefore less collateral damage would take place.

  Aizen lied unmoving on the ground, the magic energy from his body had dissipated and it had seemed he was back to normal. The attack from the Celestial Spirit King has done him in.

"...it's over..." Natsu dropped to his knees, the power from the King fading and his adrenaline crashing.

As soon as the threat was done, Happy came running to Natsu alongside a worried Luke. Yukino regained consciousness, Lucy helping themselves get back on their feet.

"You were so awesome!" The blond boy exclaimed, tackling Natsu in a hug before remembering his place and softly pushing away.

"Ya, but I'm pretty sure you would've defeated him with one Luke kick." The dragon slayer joked, pulling Luke back in the hug. The kid smiled in his chest.

"Thank you so much," Yukino formally bowed to the Spirit King. "Without your help we would've had made it this far."

"We would've been goners without you, stache man!" The pinkette agreed, a grin upon his face.

"Aye!"

"It's all thanks to your friend, Lucy." The Spirit King proudly booms. "Her smart thinking allowed myself to pass through to this world." 

The blonde flushed at the statement. "A-ah, no...this was all my fault, really..."

"Nah, Luce! It was that bastard Aizen's fault for messing around!" Natsu refuted, still enthusiastic as ever.

  She blushed further at his statement, almost forgetting this was one of the first interactions they had in years. And he was still the same.

  The King cleared his throat. "I must be on my way now. I'll leave you guys to sort things out." He turns towards the Celestial Gate, ready to pass through.

"Thanks again, man!" Natsu calls out, waving his hands along with Luke.

"Yes thank you!"

"Bye!"

The Celestial Spirit King turns back and smiles. "Farewell."

***
  One more chapter to go!! Next part will be about tying lose ends and addressing the elephant in the room. Congrats on the ppl who figured out how the out come would be! ^_^ 
After Lucy told Aizen that the King would be on their side, he kinda took it to heart a bit and decided not to go through with the whole door opening, hence why he only wanted a crack!  Thank you for sticking around!
~NaLu4Lyfe03