A/N: I'm not going to call this my END theory. This is just a drabble I wrote because I got the idea and I felt the urge to write it. It's not even really a one-shot as much as a drabble so bear with me.

Natsu never loved Lucy.

Or if he had, he didn't ever realize it.

Everyone thought they weren't going to find out though, at least that is what they were thinking as they watched the scene unfold with horror in their eyes. It wasn't how this was suppose to go. None of their plan had worked, and everything had failed them in the end. Why? Well, END was awoken, but the worst part about it, was the reveal itself.

Erza knew Natsu was powerful.

Gray knew Natsu was powerful.

Heck, even Laxus and Gramps knew Natsu was powerful.

But no one could have predicted this.

Natsu...

...was END.

Lucy had the worst reaction of all. Her eyes were wide, quickly filling with tears she was forcing herself to hold inside. Her mouth was wide open but no sound came out as she watched her best friend turn into END. It made sense, thinking about it. END was a flame demon. Natsu was a fire dragon slayer. The demons true forms were called Etherious. When you took Natsu's initials of ND and put Etherious in front of it, you got END. Still, no one would have ever thought that dense, happy-go-lucky Natsu would be the demon they were all determined to defeat.

It broke Lucy's heart.

But she couldn't kill him. Not Natsu. And she wouldn't let anyone else kill him either. He was still Natsu, still the best friend who saved her on multiple occasions, the same childish boy who got motion sickness and who had uprooted a tree for her to see when she was sick. Even with those horns curling from his spiky pink hair, and the black tendrils slowly appearing on his tanned skin, or the way his eyes seemed to change into a demeaning crimson color. A light pattern of scales were under his eyes, on his cheekbones. If someone didn't know better they'd mistake them for strange freckles.

END's deep red eyes were scanning the group of Fairies, an evil smirk pulling at his lips. The other members of Tartaros were slowly trickling in behind him, victory dancing in their eyes.. With Zeref's most powerful demon woken, nothing could stop them. At least, that is how it seemed to be, from the eyes of both sides - Fairies and Demons.

"Natsu!"

No one was able to stop her.

Lucy ran up to the demon known as END, tears trickling down her cheeks. She couldn't bear to see Natsu like this, it just tore her to shreds. At a young age, she lost her mother, and was ignored by her father. She had no friends. No real family. But then, on that amazing day, she met Natsu - the boy who gave her all of that and more. He saved her. Now it was her turn to save him.

However, Mard Geer was faster than Lucy, and he quickly sent a hit to her stomach that sent her flying into a rock wall. A scream of pain left Lucy's lips, but it was less because of the physical impact and more because of the pain of losing her best friend. No... Natsu was more than that... She didn't just lose her best friend, but she lost the boy she had fallen in love with.. The boy who was always there to put a smile on her face, who encouraged her to never give up.

Much to everyone's surprise, the demon END moved quicker than the speed of light, and had Mard Geer on the ground, squashed beneath one of his feet. "Why the hell did you just do that?" He growled, seemingly angry. No one else around them could understand entirely END was mad at one of his own? He was a demon, so that wasn't surprising, but it just seemed a bit strange.

"S-Sorry, Master." Mard Geer managed to get out.

END's beady eyes looked over to the Fairy Tail members, and he gave them a smirk. "Wouldn't you all love to know what I thought about you?" He was finding amusement in this.

"Gray Fullbuster." END says, looking at the ice-demon slayer first. "Worthy opponent, massive pervert, has a complex situation with Juvia... eh. Nothing entertaining." He says, waving a hand as if in dismissal. "Erza Scarlet." END says, a smirk playing on his features. "Would have loved to beat you, not to prove anyone right, but to prove I could protect those I cared about. Always thought you were brave and courageous, and yet at the same time you were annoying and bossy." He laughed a bit at their expressions.

"I could go through this all day. However, we have more important matters to attend to." END says, his voice the same as Natsu's, but no more was the happy cheery tone.

"What about the Fairies, Master? What would you like us to do with them?"

END looked over at Lucy, who was looking at him with tears in her eyes, her body trembling with effort as she fought to get to her feet, to stand up once again. It was an admirable effort, to say the least.

"Let them be. It would make her sad if we destroyed them, and we can't have that." END replies in a bit of a monotone. Everyone around seemed to be confused - even Mard Geer, who was now up on his feet and brushing himself off - when he said this. He let out a bit of a laugh.

"You guys are all so naïve. You really think Natsu was the one who cared for Lucy? That he was smart enough to realize what he felt?" END was amused by this. "It was always me. When she was in trouble, I gave him the power to protect her. Those brief moments where his enemies believed him to be a monster. Well, who else other than the most ferocious of them all?" He was very amused by the shocked expressions on everyone's faces. Jackal seemed to be putting two and two together; he had messed with Lucy, so END gave Natsu the power to beat him. Hurting Lucy was unacceptable.

"Therefore, you will all be punished." END says, giving a dangerous glare to each of the members of Tartaros. "You must know the consequences of messing with her."

"Y-Yes, Master END." They all say in unison. Music to his ears.

With a grace no one would expect from hot-headed Natsu, the demon walked over to where Lucy was and picked her up in his arms bridal style. No one tried to stop him, which he was perfectly content with, because it meant he wouldn't have to do anything to the Fairies. He'd have to remind himself that these petty humans were important to Lucy, and because Lucy was important to him, he couldn't destroy them. No matter how much he was itching to use the curses he had in store.

"Are you alright, my love?" END asks, looking down at Lucy with a gaze that would be considered hard if you didn't know how lethal a demons glare could be. This look was soft for a demon such as END. He was still Natsu. It's not like Natsu was possessed by END. END was Natsu. Natsu was END. It is just that END was dormant for so long, and he was slowly awoken when Natsu's protectiveness over Lucy started. Soon it had become END's protectiveness.

He wasn't sure how it had happened, but it seemed to be everything about her. The way she would smile at him, the way she looked at him so full of faith and hope. It was how she laughed and how she got annoyed when he would show up at her house unannounced. Or when she cared about others - even if they did her wrong, and how she forgave them and wanted to help them. It was in the way that when END had taken over, given Natsu the power to protect her and turning into a monster-like being, she would just smile, and be glad he was alive. How she wasn't scared of him. The way she would hug him and make sure he was safe when he went to do something stupid.

Sure, all of these were more towards Natsu, but END was a part of Natsu. The dormant part that was brought to consciousness when she was in danger.

"W-Where is Natsu? What have you done with him?" Lucy cried out defiantly, giving him that brown glare that END loved.

"I am Natsu." He replies calmly, looking at her without really reacting much to her glare. "I'm just the part of Natsu who was never fully awake."

"I want Natsu back! Give him back!" She didn't seem to believe him, which was a bit annoying. END was a hot-head through and through. He was Natsu, after all. But this was Lucy, and it's not like he would do anything to hurt her.

"Luce, I am Natsu. Come with me...Come with Tartaros." He encourages, but it almost came out more like a command.

"No." Lucy says, forcing her way out of END's grasp. His eyes widened a little in surprise. END was not use to being told no. Not by anyone. No one told END no. He was the most lethal of all of Zeref's demons. Zeref's little brother. No one dared to tell him no.

His eyes narrowed after a moment and he grabbed her arm, his grip tight and painful. He wasn't in the mood to play any kind of game right now. "You are coming with us." He says, his voice calm and stern. It was more terrifying than if he had started yelling.

"No. I won't. I'm going to get Natsu back." Lucy said determinedly, and looked into END's beady red eyes. "Natsu..." Her voice cracked a little. "I know you're in there. Don't let him take control of you. You have to keep fighting. Remember? Never give up." Her voice was soft. It was annoying.

"I told you. I. Am. Natsu." END growls, getting frustrated. In this frustration, he threw Lucy into a rock wall with a force that caused her small body to crash through it and break it. Her body was lying on the ground, hand seemingly falling on the ground in slow motion. In that moment, images flashed through Natsu's head.

Future Lucy dying, the tears in her eyes, the way she wanted to see present Lucy's guild mark. The way she had looked at Natsu when she had seen him again - that was unforgettable - and most of all... the way he had felt unbelievable rage, how he had promised that no one was going to steal her future. He would make sure of that.

But now...

Her body wasn't moving. It didn't even look like her chest was rising and falling to breath.

"LUCY!" He screamed, red eyes flickering back to his original black color. Stumbling in the usual Natsu manner, he rushed over to her side, quickly pulling her into his arms. " . .No. Lucy wake up. WAKE UP!" He screams, tears in his eyes as he shakes her body. It was hard to tell if she was alive, but it really didn't seem like she was. Nothing said she was alive at all.

"No...No..." His voice was a broken whisper, tears sliding down his cheeks as he looked at her. One of his hands reached over and grabbed hers, the one with her guild mark. Pink. Like his hair. He remembered the day she got it. She'd been so excited to show it to him, and yet he hadn't really cared. Not like it was a big deal, she was just a new member at the time. But somehow she had gotten through to him. The Natsu who was never even aware that girls were not the same gender as males. She was suddenly - faster than he had ever thought possible - the most important thing to protect.

Right now... Right now this was his fault. She was dead. Because of him.

The memories seemed to come one after the other, each with a blow more painful than the last.

That time on Tenrou island, when Lucy wouldn't run, wouldn't get away. And though she was being beaten senseless she had smiled and refused to leave him. She was always there for him, through thick and thin, and she had never left his side. His heart shattered at the memory, and Natsu wrapped his arms around her limp body and held her close to him.

"You can't be gone, Luce. Come back." He sobbed. Behind him he could hear all of Fairy Tail breaking down, and he could tell that the members of Tartaros were unsure of what to do. Natsu was still END, after all. He looked down at Lucy, only paying attention to her, but looking up protectively as he heard footsteps.

"N-Nat...su?"

Natsu thought he was hearing things, but sure enough, when he looked back down, there were a pair of brown eyes looking back at him. Relief flooded through his body, and he pulled Lucy closer, pressing his lips feverishly against hers. She tensed at first, obviously shocked, but then she relaxed.

It wasn't a very long or sweet kiss, and when Natsu pulled back he rested his forehead against hers. "Lucy you scared me." He whispers softly, looking at her with those familiar gentle black eyes. Lucy knew this was her Natsu, but she was surprised. Lucy had never thought Natsu was scared of anything. He sure didn't act nor seem like anything scared him - except for maybe Erza.

"S-Sorry." She manages to get out. Though she wasn't dead at the moment, she would be if someone didn't start treating her.

"No, Luce. I'm sorry. This is all my fault. I'm so, so sorry." Natsu says, nuzzling his nose into her neck and holding onto her, sobbing. He pulls himself together though, because he knew he had to. A smile formed on his lips, his canines showing. "I'm glad you're not dead, Luce." He says, and then gets slightly more serious. "I love you, Luce." He says, brushing some of her hair out of her face. The blush on her face causes him to chuckle a bit.

"I...Love...You...Too...Natsu.." Lucy gets out, one word at a time. Natsu hadn't even realized that Wendy was kneeling next to him and using her magic on Lucy. He had been so absorbed in the moment that he hadn't realized all of Fairy Tail was surrounding them.

It was over though, and that was good.

Lucy was safe.

Lucy lived.

But he still had to face Zeref and stop him before any more of his stupid ideas got Lucy hurt. He had control over END. He would use that power to destroy Zeref... Using the demon within to save the girl he loved.

I'm coming for you, Zeref...