AN: (Disclaimer: I do not own any of these characters, I'm only stealing them to write fanfiction. They are from Nanatsu No Taizai/Seven Deadly Sins, and Shingeki no Kyojin/Attack on Titan.) For the sake of this story making sense, we're going to bump AOT's timeline just a bit, seeing as the holy war went on three thousand years, and the period was still medieval. That being said, the date of when this story takes place has close to no relevance. Also, side note – I only just started watching Attack On Titan last night, and binge watched the first 23 episodes before I thought I'd want to write a crossover fanfiction between my favourite anime of years, and my newest favourite anime. I've read the manga and watched the anime for the sins, but I haven't even finished the first season of attack on titan, so if some things do get explained – for example, the origin of the titans and the creation of the walls - I do not know about them and have taken some creative liberties. I also absolutely love evil Meliodas. So here's a story that takes place before he met Elizabeth and was still the general of the demon army. This will be a two-shot story, maybe even three if I feel like it: the next one is bound to be longer than this one at it really is just setting the story. Reading on you'd figure out that this chapter has been written from Meliodas' perspective. The next one is from Eren's. Enjoy!!

Humans. They were the weakest of all the five races. Truthfully, Meliodas had no idea why his father seemed so passionate about ridding Britannia of them as a whole. Whenever he heard the Demon King speak about them and their inferiority, his tone was always laced with this disdain and loathing that Meliodas just didn't think they deserved. They were pathetic, yes, but humanity had never actually engaged the demon race in combat once in Meliodas' life. At two hundred and forty six, he had yet to see a human stand against a demon with any murderous intent. The few he had actually crossed paths with before he had devoured their souls would stand there trembling, resolve highlighting their features.

It was as if they all knew they were going to die.

When he was younger, he had relished in their fear. But after first encounters with humans – even when he did mean no harm to them – their fleeing at the sight of the demon prince and the mark he bore had him growing tired of it. Humans were boring. Weak. Easy to kill. He felt personally offended when he found out that disposing of a few of them was the task the Demon King had assigned to him and his troop this time, this offence blatant in the faces of his teammates too.

Around one hundred years ago, the demon king had asked for something similar to this too. Not just mere raiding of a few human villages, his father had ordered a purge. This resentment he had for humans Meliodas would never wish on his worst enemy, not even on the goddess clan. This focus, Meliodas realised, stemmed from the Demon King's feelings of envy toward humans. Not even in three thousand years would he figure out why though. There was nothing to be envious of; they were a pitiful excuse for a race. But he never questioned it either, and just obeyed his father like he had his whole life.

That century ago, however, he had been a lazy teenager. The prince of the demon realm just wanted it over and done with fast, and said the commandments could use any means they wanted to kill off human beings. And so they did.

Melascula had invoked that scary spell of hers to bring back the souls of the dead who still had grudges for the living. This wiped out many unsuspecting life forces, and sustained her fully when she took in the souls of all who were lost. She had giggled at those whose eyes burnt in her presence, having lost belief in whatever being or thing they used to have faith in when watching her go through them mercilessly. Galand had done things the old fashioned way, him being the senior of the Ten Commandments, and had slaughtered humans individually, one by one, prolonging their deaths. Monspiet devastated several cities at once, wiping them clean off Britannia with his hell blaze and fires of purgatory manipulation. Derieri couldn't care less about the violence of it all, her energy being something Meliodas only witnessed springing to life when a real threat posed itself: he understood. He did the same. Aranak rampaged, Zeno accompanying him. Grayroad had lingered back in the demon realm, not wanting to be a burden to her allies in case her commandment effected them. Gowther had found a herd of giants to play with. It wasn't long until he had sent them in the direction of human towns.

At the time, Meliodas was not permitted to join in on the fighting: Chandler had made sure of it. Zeldris too, although they both still were given the commandments of Love and Piety, they were much too young to be fighting just yet, and if the two princes perished during a one-sided war against the humans.. well, that would just be embarrassing.

A century later, another decree for the slaughter of humans being sent out, it had just lost it's appeal. The goddesses had been formidable opponents, but this was just pure genocide. Meliodas lacked a moral compass, but he could feel it in his gut that this was unfair. They were powerless.

Having fought on the front lines against goddesses before, he knew that they didn't think too fondly of human beings either. Honestly, Meliodas couldn't stand that clan, but not for the same reasons as the rest of the demons. They always thought they were better than everyone else, looking down on all the other races as though they were just mess on the bottom of their shoes. But they never attacked humans on purpose – they mostly left them alone, unless they had been collateral damage in a battle against his own kind. He knew that as a result of the mass slaughter that had occurred a century ago, the goddess clan had become more sympathetic toward the human race, the Supreme Deity's daughter even leaving her comfortable home in the heavens to help the humans from being eradicated entirely. For the decades to come, the troops lead out by that one high-ranked goddess had helped in the building of these walls around a large portion of Britannia. This place inhabited the few remaining humans, keeping them protected from the demons. The Supreme Deity's daughter even stood guard at the largest gate that connected the humans with the rest of Britannia. When construction was still undergoing, she had made it intentional that the walls only ever had one exit and entrance, so that defending what was inside wouldn't be as hard. She turned away low-level demons that had ventured there on a whim without even needing to exchange blows.

And despite her heritage, Meliodas was almost impressed. In human years, he had been equivalent to almost a fifteen year old boy. His stubbornness was at it's peak, and he wanted nothing more than to confront the goddess head on and take her down, but his father had warned him against it.

She had stood there six days and six nights with no rest, and was able to hold her own against the people who dared to challenge her. It was only a herd of giants that had managed to garner her attention away from what she had made her own duty. They seemed way too determined to get in, unnaturally so. It was as if their sense of self had been lost, as well as their feelings and vulnerability to pain. They didn't comprehend anything she was saying to them to get them to leave, and on the seventh day, she was gone. As well as those titans.

What had inspired the Demon King to go after the humans in their concentrated spot, was the discovery of one of these giants. The goddess from years ago had managed to conceal the humans' dwelling place from the higher-ranked demons, similar to how the goddesses could conceal their entrance to goddess realm. But that didn't mean it was invisible.

What Gowther did to them – or rather, what he didn't – seemed to change them entirely. The giant race did indeed have long lifespans, and many of them had chosen to linger menacingly around the wall to the human country. It didn't take long for Meliodas to piece together that these creatures had been inflicted with Gowther's commandment of selflessness, and had also fallen victim to his Invasion ability. On the demon king's orders, he had converted every one of these giants' thoughts to that of an insatiable hunger for humans.

"They all desired for each other to live when I arrived," Gowther told him. "Cruel as it may be, even the desire for one to live counts as a desire of selfishness." His voice had lowered considerably, and Meliodas felt strange for the pangs of sympathy that had gone through him.

The mage had been imprisoned on his father's command, and had been bestowed his commandment as a way to restrict him and limit his abilities. The doll of his creation seemed to convey the emotions the trapped mage must be feeling, and Meliodas couldn't help but feel… bad?

The captured titan Dereri held on a string of darkness lead them directly to the foot of the wall.

Meliodas couldn't help but stick his nose up; the design of it was entirely flawed. For demons who could conjure up wings whenever they saw fit, a sty with no roof was stupid on that goddess' behalf. And to think he spent most of his life honing his skills to face off with her, holding her in high regards in his mind, when she didn't even think of the possibility that higer-ups would ever find her harboured victims and be able to simply fly over the walls. He scoffed, looking up the wall.

It had to be fifty metres tall in all.

No bother.