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Undertale AU Writing Prompts

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“Sometimes I forget that you can die. Sometimes I don’t want to remember.”

Those words echoed in Cross’ mind like someone shouting them in the dark, cavernous ravine of his mind. Nightmare didn’t sleep well last night - he never did - but Cross found him up and about early in the morning, while Error continued to sleep soundly in his bed.


Cross shook his head, trying to rid the name that jabbed at his soul and reopened a wound Cross had carefully concealed so as not to start bawling his eyes out.

At five in the morning, approximately a few hours before he would normally wake up, Cross had dragged himself out of bed upon hearing a noise in the kitchen, knowing it was Nightmare but still too paranoid to not check and make sure JR hadn't silently found them, like some sort of demonic angel in the night. He reached the bottom of the stairs and lo and behold there he stood, the short skeleton in all his glory, his purple cape flung carelessly over his shoulders and dark circles beneath his eyes, the smell of coffee drifting aimlessly through the dimly lit kitchen.


“Morning, Cross,” the skeleton in question said without looking up from the faucet that poured water into the coffee pot sitting in the sink, his arms crossed and his eyes zoning in and out until he finally shut off the water and took the pot out of the sink.

Cross awkwardly sat at the kitchen table, letting the silence sink in as he watched Nightmare’s back who quietly ambled about the kitchen, brewing coffee, taking out a mug, then hesitantly grabbing one more before closing the cupboard with a muffled thud. Nightmare set the cups down and turned around, leaning on the counter and staring at the floor with a slight frown, his eyes drooping closed every so often before he jerked himself up again. A moment later, a quiet beep broke the silence and Nightmare sprung out of his stupor. He poured both skeletons a cup of coffee. He passed one mug to Cross and picked up his own mug, sitting down at the wooden table across from Cross.

Cross stared at Nightmare as his friend slowly sipped his coffee. “You look like hell,” he stated.

“I’ve seen hell. It’s nothing compared to this,” the other mumbled before taking another sip of coffee.

Cross glanced out the window near the table, seeing how the sun barely peeked over the horizon, a blue hue stretching over the black sky as the stars slowly began to disappear. He turned his head away from the window. “What’re you doing up so early in the morning? Did you not sleep last night?”

A disgruntled look from Nightmare told him everything he needed to know.

“Ah.” He picked at his fingernails, then wrapped his fingers around his steaming mug, not wanting to encroach on the topic, but unwilling to let his best friend suffer alone. “Same nightmare?” he asked instead, hesitant yet curious.

Nightmare paused before shaking his head. “No.” He set his coffee aside before folding his arms on the table and slouching even further, closing his eyes. “It wasn’t like the usual. Unfortunately, it was...worse.”

And then he said it. The two short sentences that continued to taunt and mock Cross ever since...

He sucked in a breath and bit his tongue. Hard.

It rattled Cross to hear such sad words come from a usually uptight person, especially when that person’s voice quivered and he had to look away before going back to his normal stone face. His heart sunk and he sipped some of his untouched coffee in an attempt to distract himself. The distraction mildly helped.

Nightmare quickly changed the topic, saying nothing more about his night, and Cross was thankful for that because he didn’t need to know any more about the nightmare. He didn’t want to know. Thinking about death sent shivers down his spine; of not knowing how or when it will happen, and being so close to death already what with him and his friends being labeled criminals by the entire Multiverse, the fear dawned on Cross in his darkest moments, like some sort of animal lurking in the shadows, circling him, waiting. Watching. Always watching.

Cross rubbed his arms and walked faster through the forest, hoodie pulled up and head down despite the lack of civilization or anyone in general who could recognize him, picking through his day and wondering how he got to where he was. How he could be so careless.

Unfortunately, the rest of his day contained nothing of interest. Hours after their little talk, Error stumbled down the stairs, groggy and grumpy as he usually was in the morning, his glasses crooked and his pajama pants sliding down his waist, covering his feet as he shuffled through the kitchen, greedily helping himself to a huge serving of coffee Nightmare made earlier that morning. Not too long after that, they played video games, Cross losing (obviously), sat around, not really do anything particularly exciting. The three of them were quiet, not saying anything to one another, simply relaxing and enjoying the peacefulness of their afternoon. Even Kevin seemed less talkative than he usually was, clucking to himself every now and then outside the living room window and pecking at the dirt in his coop. They couldn’t be more content with themselves. It was their version of a lazy Sunday.

Until Cross suggest they break into JR.

“Hell no,” Nightmare immediately responded, sprawled out on the couch and boredly staring at the show playing on the TV, the volume turned down to a whisper. “It’s my turn to clean the house and I’m not letting this shack go another day without a dusting.”

Cross raised his eyebrows at his friend who would normally jump at the opportunity to bug his brother relentlessly, but shrugged it off and turned expectantly towards Error, who sat cross-legged on his favorite rocking chair next to the couch, knitting. “Error?”

Error set his knitting needles and string aside, stretching his arms above his head with a grunt and, letting his arms fall to his lap, shrugged. “Sure. Why not?”

Now Cross could list a thousand reasons why that was a horrible idea. His mind lingered on the memory, his eyes trying desperately to memorize Error’s every feature. They way the blue lines on his cheeks curved gracefully from his eyes to the bottom of his jaw. His mismatched eyes, one white and the other orange with a white pinprick in the middle. His genuine smile. His red, round glasses. His nimble fingers as he cleverly wove his strings into something beautiful or as he furiously jammed the buttons on a video game controller, eager to win whatever game they were playing. The contrast of the colors on his fingers against his black, fingerless gloves. Even if he was the quietest among them, he was one of the strongest and best people Cross knew. Probably the cheeriest, most sincere, and kind-hearted person in his life.

He stepped out of the bramble on the forest floor, bending down slightly to brush any stray leaves away and assess the small scratches on the exposed bone of his legs, finally looking up at the house at the other end of the small clearing, practically engulfed by the forest. Yellow light flooded through the windows at the front of the house in the dim evening light. A breeze blew past Cross and he trembled, pulling his white jacket closer to him, though it didn’t help much. He sure hated the dropping temperature that came with autumn. Cross watched Nightmare’s silhouette from where he stood, presumably cooking dinner, and Cross backed away into the safety of the forest. He didn’t want to tell Nightmare, but he knew he had to. Who knew a few yards walk could feel like an ocean away?

Butterflies fluttered where his stomach would be and he fidgeted, anxiously racking his brain for something to say. Despite how Nightmare insists that he’s fine in the most heart-wrenching situations, Cross knows that he’s not okay. He definitely won’t be okay now. Not after hearing that his best friend, the person who stayed by his side no matter what, could be taken down as a gleaming sword thrust through his chest-

Cross shuddered and his body swayed back and forth, the world tilting to and fro until he stumbled back and hit a tree, bark scraping and cutting his jacket as he slid down the trunk, but he didn’t care. As soon as he walked through that battered front door, Nightmare would sense Cross’ intense feelings and he’d know - he’d know - that something was up. It was bound to happen sooner or later. He couldn’t sit in this forest forever and hope all his problems will go away. Cross sighed and abruptly stood up again, marching out of the forest and to the front porch, up the creaky steps that were always broken and bent, across the porch, to the door.

He could do this.

He lifted up a bony hand and rested it on the rusty doorknob.

He could do this. Nightmare had to know one way or another.

He clutched the doorknob and turned it.

The smell of soup greeted him as he stepped into the house, his gaze drifting about until it landed on Nightmare, who leaned over the table he had set with bowls and bread and everything.

A table for three.

“Hey Cross.” He glanced up and frowned after setting a pile of napkins in the middle of their small table. “Where’s Error?”

And then he couldn’t take it anymore.

Cross started crying.