"i gotta say, pal. i really wanted to be wrong about this. i mean really wanted to be. but here you are, trying to sell the same corny shtick to someone else."
Sans glanced at the monster sprawled out on the ground. His white fur and humanoid build made Sans assume he was from Snowdin.
Sans attempted to scowl. "was he not feeling cooperative at first? did you rough him up to put him in a more talkative mood? i thought chara was the violent one. you picking up his bad habits?"
The child's eyes darted from Sans to the fallen monster.
Sans checked his watch as the kid formulated an excuse. 2805. Good.
"This isn't what you think it is, Sans. I didn't hurt Asriel. Something's happening to him."
"asriel?" The name sent a rusted memory into motion. "asriel, the king's son, asriel? the one that died centuries ago?"
"He didn't die! Well, he did, but… He's here now. He can absorb Chara, so you don't have to."
Sans stalked over to get a better view of the monster. "you should really leave things to the professionals, kid. i'm the comedian here, remember?"
He drew close enough to look at the monster's face. He didn't know what he had expected. All he knew about Asriel were rumors and hearsay. He had to admit that the monster bore a resemblance to Asgore, but a lot of monsters looked similar.
A cloud of fear crossed the monster's face as Sans studied him. "You better stop looking at me like that or I'll—" He snapped his teeth shut to muffle the next few words.
The child propped the monster up with one arm and shielded the soul fragment with the other. "It's not a joke. This is Asriel Dreemurr, Chara's brother."
Sans crushed his surprise before it could snowball out of control. He chuckled and tilted his head. "brother, huh? ok, then. so that thing—" he pointed to the fragment "—was the first human that ever fell down here? he was the king and queen's pet project that got asriel killed and sent the whole underground into spiraling depression?"
The monster gave an almost-imperceptible shake of his head. "He wasn't a pet project, he was my…" He searched for a word and his expression suddenly shifted. He growled and bared his fangs. "He was my parasite! He ruined my life!"
"yeah, parasite sounds about right."
The child glanced between them. "Don't say that! It hurts his feelings when you call him that."
The monster cringed. "No, I didn't say—I didn't mean to say that, Frisk. I'm sorry."
Sans slid a few inches over to see if he could get a clear shot at the fragment, but the kid held it too closely. The idea of punching a hole through him with a blaster beam appeared in Sans' head, but he dismissed it immediately. That wasn't an option. It just wasn't.
Sans continued to examine the monster. "so, if you're the prince then why are you here? shouldn't you have inherited asgore's magic and grown up after all this time? this is a little hard to follow, especially since so many people watched you die."
The monster gave Sans a calculating look, but said nothing.
"He was brought back to life with a new body," said the kid.
"really? do people just grow replacement monster bodies in their gardens nowadays?"
"Well, if you count flowers, then yeah, I guess they do." A fragile smile touched the kid's face.
The monster stiffened. "Shut up, you idiot!"
"flowers? what color, if you don't mind me asking?" Sans could feel his magic eye widening.
"Uh, yellow. Why?"
Sans nodded as everything fell into place. He turned to the monster. "so you were the talking flower that was messing with pap? the one that tried to kill everyone yesterday? looks like tori and asgore need to take some parenting classes. it's a bad sign when both your children grow up to be serial killers."
The kid shifted the monster out of Sans' line-of-sight. "It's not his fault! He has no soul. He can't feel anything."
"soulless? that's a pretty lame excuse. you don't have to feel something to know if it's right or wrong." A burning sensation wormed through Sans' head as he poured extra magic into his eye. "were you really about to combine these two, frisk? if i hadn't shown up, would you have mashed these two killers together, crossed your fingers, and hoped that something good would have come out of it?"
"If I don't hope, then no one will."
Sans scoffed. "come on, this is all a bit too optimistic, don't you think? even for you…" He cobbled a Gaster blaster together with the dregs of his magic. The thing was deformed. The grin lacked a few teeth, and the skull was cracked all over. The act nearly sent Sans into pain spasms. He fought through it and straightened his spine. "put the fragment on the ground and step away from the monster, frisk. i won't ask twice."
The kid might as well have been made of stone.
"Do what he says," whispered the monster. "Don't you dare!—" He grunted. "Don't worry about me. It's better this way… for everyone."
"This will work, Sans." The kid's expression was stoic and unreadable.
Sans began to charge the blaster. "i can't take that chance."
"…Then I will."
The child slammed the soul fragment onto the monster's chest. It strobed a violent red as it sank through the sweater and into the monster's body.
Sans roared and fired the blaster. It ripped through the air like a sine wave, ending in an erratic lightning bolt and striking the two figures.
Light engulfed the cavern.
Asriel sat cross-legged on a featureless grayscape. It was completely flat and extended into infinity. He scanned in every direction, but didn't see or hear anything, except for the faint echo of his own breathing.
"Hello?"
Nothing.
The vacantness crushed in on him like a physical force.
"Anyone?"
He began to rub at his ears and rock back and forth.
A voice cut the silence.
"You still do that after all these years? Even though I gave you so much grief for it."
Asriel spun around and climbed to a kneeling position.
A thin child with droopy, caramel-colored hair stood before him. He picked at the sleeve of his green and yellow sweater while staring at his feet. "Hey."
Asriel gawked for a full minute. "Chara?"
"Yeah, it's me, well… what's left of me."
An impulse to touch Chara ran through Asriel. He had already risen to his feet and taken a few steps before he came to his senses. He stopped. "What is this place? Why are you here?"
"We're in you, I think. Frisk probably came up with a dumb idea." Chara looked around sheepishly. "It's not quite like last time, is it? When we, um, when I…" The words died away, but a thought drifted towards Asriel like a wind-tossed leaf. …Tried to kill those humans.
The surface of the grayscape rippled and scenery materialized around them. They were suddenly in a black-and-white recreation of The Heart. Asriel spotted the twisted hulk of the destroyed harvester over Chara's shoulder.
Chara rubbed at the back of his neck. "Yeah, uh, this place. You've got a pretty vivid memory of it."
The grayscape rippled a second time, and the hills started burning. Screams filled the air. They were compressed and distorted, as if they were coming out of damaged speakers. A crowd of humans bloomed out of the fields and began to cower at the approach of an unseen antagonist.
"I get it, Asriel. You don't have to show me this." Chara began to squirm.
One of the humans separated itself from the group and held up a weapon.
"Asriel, PLEASE STOP!"
The hills, the fire, and the humans all liquefied and splashed down around their feet. The grayscape stilled like a frozen pond.
Chara sat down and wrapped his arms around his legs. He closed his eyes and let out a long exhale. "That hurt a lot more than I thought it would."
Asriel smothered the urge to apologize and clenched his paws into fists. "What am I supposed to say, Chara? What am I supposed to do? Frisk said you're a better person now, that all the time in the loops changed you. But that's not how it works! Look at what time turned me into!"
The grayscape undulated like hurricane waters. Hundreds of still-shot images of Flowey protruded from the waves and depicted his killings. A look of sick glee plastered his face as he impaled Toriel, Papyrus, Undyne, and nearly every other creature in the underground.
Chara's tired eyes scanned the waves as it all played out, but he said nothing.
"Do you see?" Asriel whispered. "That is us. That is what we are. No amount of apologies or regret is going to change that. So answer me, do we even deserve to come back? This chance that Frisk gave us, do we even have the right to take it?"
Chara rose and tilted his head to look up at the vacant, gray expanse. "No, we don't. Things would be a lot simpler if we stopped existing."
"Then, should we just—"
"I had this conversation not too long ago. I was on your side of things, talking to a stubborn kid. I explained all of this to him, tallied my sins on an invisible chalkboard. But he ignored it. Every word. All he said he didn't want me to disappear. Because it would have been too sad…"
Asriel's shoulders drooped. "That's a really childish way of looking at things…"
Chara closed the gap between them in four brisk steps and crushed Asriel in an embrace. He buried his face into Asriel's shoulder and leaked hot tears onto his sweater. "I'm so sorry I ruined your life. I turned you into a killer just like me."
By their own will, Asriel's arms wrapped around Chara's shoulders to return the hug. "I missed you. I was always so scared when you weren't around."
They held the pose for a long time. Chara's voice came out muffled and small. "It's just not fair. For me to get another chance while you just fade away." He relaxed the hug and pushed Asriel to arm's length, looking him in the eyes for the first time. "Let's go back. Together."
"What if it doesn't work? What if everything goes wrong?"
"If Frisk saved everyone once, then he can do it again, can't he?"
Asriel wiped his eyes on the back of his paws. "I want to believe you, Chara. So badly. Please…"
The grayscape bled away like ink soaking through a piece of paper. Blotches of reality peeked through, and the cavern slowly came into existence.
A confusing jumble of sensations struck Asriel in quick succession. First came a feeling of fullness and warmth. It radiated from his chest and flooded his whole body. He looked down to see a pale, red heart glowing through his sweater. The second was the smell of burning ozone that permeated the cavern. Third was the kid's touch. He cradled Asriel's torso, and hunched his own body like a shield.
The fourth was the sound of Sans' screams.
"no! no! why did you do that, kid! why! you didn't owe them anything! least of all this!"
Asriel looked into the child's face. "Frisk?..."
The kid's body shook and he took his breaths in short gasps. Their eyes locked and he showed his teeth in a triumphant grin. They were stained crimson. A dribble of red darted from the corner of his mouth and down his throat. "I told you guys it would work. I knew. You just h—had to believe."
Life left him, and he began to slump to the ground.
Asriel grabbed the child's sweater and held him upright. It was then that he finally noticed the gaping blaster wound in the center of the kid's chest.
Author's Note: Don't hate me... please? :)