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Promises were a strange thing.
Some held these agreements highly, never forgetting the ones they made, while others would quickly forget and just as easily break them.
For a Sans.
It was thought that a Sans promise was something that was set in stone. However, most not remember, that while he said he did not like making promises, he did break them in the end. By killing Frisk.
And yet, this motion of a Sans was a keeper of promises and some sort of code of honour that was a setting for all Sanses, that somehow gotten written down in the Multiverse' main True settings.
Error growls, he hated it.
Just because Sans said 'this is why i don't like making promises.' or that 'you'll be dead where you stand' if he had had not made that promise. Sans had burned out long ago and he was not killing them to keep the promise.
OF course, he was sure that some Voice out there had made a character essay about the matter. But even if Sans was a protector of all promises, why did the rotten glitches of the multiverse use that as a get-out-of-jail-free card.
'Sanses' Promise'.
A dumb phrase that was going around the Multiverses' hub worlds and somehow reached the Gloom and Doom Boys.
Error growls out, glaring at the three offensive glitches that belonged to Nightmare- Killer, Dust and Horror.
They were raiding a universe and just used that phrase when dealing with the local Sans and that Sans believed them when they said 'Sanses' Promise'. And the thing was, they followed it through and kept their promise.
"*so destroyer. your only complaint is that they kept their promise?" Nightmare questions with a raised brow, sitting behind his desk, looking between the Gloom and Doom Boys and then to the ERROR.
"*yes! ya meant to be the bad guys!" Error roars out, glitching wildly as he points to the giggling trio, "the villains! how could this happen!?!" he stamps his foot down in outrage.
"*destroyer. do you not think that even 'bad guy' can have a sense of honour?" Nightmare growls out him, his darkness that surrounds his body flowing faster, a sign of just how displeased he was.
"*shut it! i've read lots of stories of bad guys! and ya shouldn't be acting this way!" Error explains with large lag, showing his own displeasure.
"*well then destroyer. write down all how villains should behave." Nightmare told him with a smirk, "so i can screw it up and throw it away."
The Gloom and Doom Boys chuckle at this.
Error lets out a glitchy growl. Reaching his hands up, he claws at his sockets, rips them down his cheeks, leaving a trail of blue- what most do not know, was that the ERROR's blood was blue and the strings were not just coming from his sockets but the cheeks were it kept digging into.
Nightmare was now on edge with his display.
"*boys. leave." Nightmare told them and they all shortcut away, and the dark guardian rose from his seat, "destroyer. i would advise against attacking me. you would do well to remember we have an agreement. and we are currently allies."
Error pauses, wishing he had never agreed to this. However, the number of characters coming out of their universes and into the Multiverse was growing with each year, along with OP characters that were making a name for themselves.
"*i am the error! the destroyer of worlds!" Error glitches out darkly, glaring at the creature of darkness, "the evilest and beautiful skeleton in the multiverse! ya think ya can beat me?!"
Nightmare stood there, staring at him with a calculating gaze.
"*destroyer." Nightmare hisses out, his four tentacles appear from behind him, "i shall not warn you again. we are allies. remember. attacking me is the same as making me into your adversary. if i recall. you have enough of those."
Error pauses... he had gone over the top once more.
Over the past few years, the ERROR had been thinking more and more and realizing that he was insane. The issue with that, the more he sees himself as truly insane, the more he did not want to be in the world. Just wanted to crawl into a hole and never leave.
Perhaps that was why he reached out to Nightmare and that was why he wanted to believe in villains so much. Error did not want to true sane.
The ERROR lowers his string-bound hands and stares to the ground- his dark thought start to engulf him-
Error blinks, something living had touched his hand and he did not freak out. Glancing down he sees a thin black string and realizes it was a part of Nightmare's darkness.
Confused, Error reaches out for it and grabs hold. It was icy cold against his burning magic, it felt like smooth mud that hummed in power.
Error follows the black string to Nightmare, who was silently observing him. The mega-glitch starts moving towards the dark creature and to his credit, Nightmare did not flinch.
Error stood in front of Nightmare, he could sense the attack coming but he did not move as the tentacles went through his back and came out his front- the Destroyer had walked around half dead and bleeding out in the past, this was nothing.
Error's hand reaches up and touches Nightmare's surprised face. The ERROR smirks at his reaction, that attack would dust a normal monster.
"*it doesn't hurt." Error explains this very important face as he runs his hand down Nightmare cheek in almost a loving manner- and he was talking about his fear of touch not the tentacles in his back.
"*destroyer." Nightmare hisses out as he comes to his senses, his face twisting into something from a real nightmare, "release me."
"*heh. nope. i'm gonna keep ya. ya mine now." Error told him with a smirk, blood starts pouring from his jaws, "ok. i won't ever question ya again. heh. sanses' promise." he even winked at his ally.
Nightmare glares at him and tries to move back, "*free me."
Error huffs loudly and releases the magic that had trapped the tentacles into his body when the strike happened.
Error had wanted someone to touch for about a year now. He never thought it would be Nightmare who he could touch without triggering him.
"*destroyer leave. i want to rethink our agreement." Nightmare growls out darkly, moving away from the ERROR.
"*just call me error." Error told him with a grin, most blood pours out and pools around his feet, "i noticed ya never call others by their names. only titles. killer ya call 'knight'. dust ya call 'defender' and horror ya call 'attacker'. and me. destroyer. i could go on." he thinks about it for a moment, "ah. that's what it is. ya won't call others by their names. 'cause ya don't want to get close to them. ya scared."
Nightmare's expression completely changed, making the ERROR blink, he wished he had his glasses on to know what emotion was. It was something from the normal for him to notice.
"*i'm right. heh. ya ain't a villain like me." Error growls out darkly, moving nearer, and was a little surprised when Nightmare backs away, "ya just a lonely monster. playing bad evil king. but deep inside. ya want others to be close to. ya want love and acceptance. right?"
Error blinks when he realizes that he had back Nightmare into a corner.
"*did i say too much?" Error wonders alone, he reaches out and touches the dark king's cheek, "play pretend all ya want. i don't care. i'm ya ally now. i meant have days when i'm completely insane. even then. forgive my outburst. i don't mean them."
Nightmare was staring at him, then turns his skull away.
"*destroyer. please leave." Nightmare says to him with much bite in it as before.
"*i'm sorry. i always destroy things..." Error told him actually feeling sad, "i can't help it. it's in my code."
Nightmare nods, seemingly getting a hold of his emotions he says firmly, "*if i can forgive my attacker trying to eat my tentacles. i can forgive the destroyer for his small transgressions."
Error grins boldly, then turns to leave but pauses.
"*by the way. nightmare." Error says with a smirk, "ya don't have to play the sans role too much. i can see ya code. half ya is taken from a swap sans. so. i ain't surprised ya like ya castle nest. or that ya ain't as lazy as the rest."
Nightmare frowns, "*a swap sans? me? and my brother?"
"*both of ya." Error told him leaning over him once more, "i like swaps. my favourite kind of sanses. don't tell anyone. our secret between allies."
Nightmare nods and moves back.
The ERROR opens a gateway and leaves that universe.
The next time Error came to Nightmare's Dark Castle, there was a yandere Swap Sans nicknamed Cleaver- they were in love with Swap Papyruses and kept jumping to different AUs in order to replay after they little love story, killing both their own counterpart and their 'true love'.
Nightmare had promised them that they would fate a Swap Papyrus that would return their love one day.
The ERROR found it amusing.