Underfell Sans X Frisk

By Hazefrost

44.7K 651 388

When Frisk falls into the Underground, she is horrified to discover the world of monsters is every bit as evi... More

Preface
Chapter 1: Skeleton In The Woods
Chapter 2: Terrified
Chapter 3: Poison Trap
Chapter 4: Hiding
Chapter 5: Almost Lust
Chapter 6: Inner Demons
Chapter 7: Ill
Chapter 8: Recovered
Chapter 9: Keep Safe
Chapter 10: Love Is Wrong Love Is Right
Chapter 11: Teeth and Lips
Chapter 12: Midnight Planning, Midnight Snacking
Chapter 13: Papyrus's Discovery
Chapter 14: Crush, Crush, Crush
Chapter 15: Flushing Blushing
Chapter 16: Argument
Chapter 17: Defiance
Chapter 19: Undyne's Wrath
Chapter 20: Another Recovery
Chapter 21: Undyne's Curiosity
Chapter 22: Alphys
Chapter 23: Drunken Sans
Chapter 24: Intimate Talk
Chapter 25: Bath
Chapter 26: Bubbles & Breasts
Chapter 27: Midnight Confessions
Chapter 28: Asgore
Chapter 29: Flowey's Rescue
Chapter 30: Peace
Epilogue

Chapter 18: Fear

988 15 4
By Hazefrost

Frisk

The bloody monster suddenly vaporized, turning into dust completely. The monster that had killed it stood over the spot where it had vanished and laughed in a menacing way.

It was a female.

Frisk felt horrified and sick at the same time, though she knew she had no idea what had happened before she arrived. Maybe the monster had attacked the laughing one, or maybe provoked her in some awful way. Monsters down there seemed to do that kind of thing. But by the sound of the killer's laughter alone Frisk guessed she had really enjoyed the kill.

I should go confront her... Frisk thought you herself. But she was frozen with terror. She couldn't imagine confronting such a wicked being, for she felt as though evil itself had manifested inside the monster. Instead she waited until the monster finished walking away. Then, without missing a beat, Chara bolted through the woods and past the town without missing a beat. She was careful to avoid traps and monsters this time as she did so, though she'd heard that Papyrus had only put a few traps up near the ruins since he had decided that maybe humans were alright. However, he still wanted to look like he was ruthless and wanted humanity to die. Frisk understood that, though she knew nobody else knew about her. She would have to tread carefully if she was to survive...she'd have to find Asgore without interacting with a single soul... it would be hard.

Sans

Anxiety pulled and Sans soul, making him increasingly more furious as the day went on.

Where the hell is Frisk?! He wondered as he and Papyrus searched outside their house frantically in search of the girl. But Sans knew damn well she wouldn't be there. Not after the conversation he'd had with her earlier. She was hell-bent on making the monsters good and bringing them to the surface again. Literally nothing would stop her from reaching the goal. Sans was furious and full of admiration at the same time. He certainly wouldn't be ballsy enough to go out and do something like that. No way was he risking his literal spine for that. He would rather get kicked by Papyrus for twelve days.

"Boss," Sans said as he shoved his hands in his pocket and watch his brother literally look beneath every rock and tree surrounding the house. "I told ya, the human isn't here."

Papyrus shot him a glare. "I'm checking every available spot before I make a decision on where to look first," He hissed before going back to looking for Frisk. "Now, Sans, hurry up and help me!"

Sans knew better than to mutter anything under his breath and nodded, helping his brother search the yard even though he knew it would be of no use.

Frisk was gone. Not dead, but she would be soon if they didn't find her. And he knew for a fact that she was nowhere near their house anymore. She would be looking for the king...

Frisk

Frisk hurried through the underground area, carefully making her way toward what she hoped was the direction of the king's castle. Her heart skipped a beat as she remembered how terrifying the king's former wife, Toriel, had been. She had been driven mad with loneliness due to her isolation and Flowey had been the one to save her. She wondered if Flowey was alright and if he was keeping the goat-monster-thingy company.

She was now walking through a luminescent cave with flowers that lit up the area and glowed. They also seemed to echo with voices, which had terrified her at first. Now she was used to it, though, and she tried to make her way carefully through the area.

"Hey, thing!" A voice sneered, causing Frisk to nearly pee herself as she spun around to face whoever had spoken. A monster in a striped shirt with only two legs and no arms was staring at her with a smirk on its face. It was smaller than her. A child. It looked like it probably bullied everyone else for fun.

"M-me?" Frisk stammered, stunned at the sight of the monster. She cursed the echoing flowers in her head. They had prevented her from being able to hear the little monster approaching.

"Yeah, you," The monster said with a snort. "They call me 'Monster Kid'." He grinned at her. "And I am the boss in these parts. Besides, Undyne, of course. And even though I am smaller than you I am going to make your life hell!"

Sans

"Stop screwing around!" Papyrus snapped impatiently as Sans lagged behind him as they walked through Snowdin. "If you want to catch that human and make sure she doesn't get into trouble, you're going to have to put in some effort into it!"

Sans nodded and picked up the pace, though he had a lack of faith that Frisk had survived. Her heart was in the right place but he had his doubts that she'd be able to hold her own, especially since she'd made it clear she refused to fight other monsters.

"Hey! Papyrus!" Undyne's voice barked.

Sans jumped and nearly ran to hide behind his brother. Undyne was...aggressive, to say the least. Yes, Papyrus was ruthless and brutal, but he was being trained by Undyne who proved to be just as, if not more, terrifying and intimidating. Right now she was fully clad in armor and was marching over to them.

"Yes?" Papyrus asked, lifting his chin as the monster who'd mentored him for years approached.

"Have you seen Monster Kid? I just killed that brat who bullied him last week." Undyne's voice was just as intimidating as her appearance...and her personality. 

"No," Papyrus replied.

"Fine, I'll look for him by the waterfall," Undyne said with a growl in her tone. "He's probably screwing around by himself there like usual. Told him I'd teach him how to disembowel an enemy. He'd need that if he was to ever encounter a human." With that, the freakishly strong female monster turned and marched away in search for Monster Kid. 

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