Power to Heal (Underfell!Sans X Reader)

16- Dr. Gaster

You are surrounded by pure darkness.

No, no. Where? I'm not dead right?! I got to get back to Sans and everyone.

You looked around frantically searching for something, anything. You spotted a soft light and ran towards it, in hindsight that probably wasn't the best idea. When you reached the light you saw a tall skeleton wearing a long black trench coat and red slacks. He had incredible red eyes, like Sans but a terrible long crack on his head leading down to his left eye.
"C-can you help me?"
"WhAtS WrOnG DeAr, A lItTlE lOsT?" You didn't answer, the way he spoke fascinated you. It was like a bad radio connection, going in and out. "CaT gOt YoUr tOnGuE?" You realized you were staring, you blushed a little and looked away. As soon as you approached the mystery skeleton you forgot where you were and what you were doing. You were filled with curiosity and questions.
"S-sorry could I ask you for your name?"
"Dr. GaStEr, KiTtEn." You realized you didn't give him your name, how rude of you, you thought.
"I'm sorry! I'm (Y-"
"I kNoW yOu QuItE wElL, (Y/n).
YoU aRe ThE yOuNg LaDy ThAt SaVeD mY sOn... BuT aT SuCh A cOsT. NoNeThElEsS yOu HaVe My ThAnKs."
"H-how- W-what do yo-" You were cut off by a pain in your chest.
"It SeEmS lIkE yOuR oUt Of TiMe, YoU MuSt FoCuS oN wHeRe YoU LiKe To gO ThEn OpEn ThAt DoOr {Dr. Gaster paused pointing to a door you could've swore wasn't there a moment ago} If YoU DoN't HuRrY YoU'lL bE StUcK In ThIs rEaLm, LiKe Me." You didn't totally understand what was going on but you felt it in your soul that you had to go. You didn't feel right leaving Dr. Gaster. You ran up to him and gave him a big hug, you felt tears fall from your face.
"Thank you, Dr. Gaster." You felt him tense but the he relaxed and hugged you back.
"CaLl mE G." You unwrapped yourself from G and wiped away your remaining tears. You walked to the door turned and waving to G. You turned back towards the door and grabbed the handle. You thought of Sans with all your heart, closing your eyes, and opened the door.
----------------------------------------------------
You snap up and immediately regret it. Everything hurts, everything. You look around and find yourself in a mess room with bottles of-

Is that mustard?

You try to stand up from the bed your in and collapse instantly. Pulling the night table down with you making a big-

-THUD-

You heard footsteps run quickly to the room. The door slammed opened, probably breaking it, and there stood Sans. "Hehe, hey. Weaker then I thought." You giggle lightly. He walk over to you and leaned down hugging you, so tight like you felt like you were going to break. Even though it hurt like freakin crazy, you deemed it worthy. You blushed from head to toe. "S-sans come on, you act like you haven't seen me in days." Sans flinched a bit at your words, your eye grew wide.

No way...

You gently removed yourself from Sans embrace and look him in his 'eyes'. "H-how long was I out?"
Sans let out a sigh, "Three weeks."
Your head was going crazy, three weeks, you were 'asleep' for 21 days. You closed your eyes and took a deep breath in and out. You try to calm yourself down.

Oh God, I have to keep it together... I might have missed a lot but I have to think about Sans, Paps, and Flowey. They were probably freaken out thinking I was never going to wake up...
I need to hold it together for them!

"H-how did I survive?" Your hands were shaking uncontrollably, Sans rest his hands on top of your's, they were warm, they made you feel safe, your hands stopped shaking.
"A friend of mine, Dr. Alphys, she took all the measurements to make sure your body stay healthy, while your soul and mind fought internally." You shook your hand acknowledging you understood.
"Okay, how about Paps and Flowey and... how is Frisk?" Sans gripped your hands tight, you tensed a bit in pain. Sans realized what he did relaxed his grip and even looked guilty.
"We don't know, that brat was gone before I could get my hands on her. As soon as you collapsed, I told Paps to take you home, but the kid was already gone. Haven't seen her since." You felt kinda relieved, you didn't know if Sans could hold back his temper and end up killing Frisk... more importantly Chara.
Sans looked at you again. You froze, your eyes grew from stock. You didn't noticed before probably because you weren't really examining him but he had a crack down his head almost exactly like G's but his didn't lead all the way to his eye. You slowly moved your hand to the crack, you touched it ever so slightly and Sans jumped a bit. You quickly pull your hand back.
"Sorry!! Ho- I mean, I thought I healed you?" You said in more of a question then a statement. Sans looked at the wall staring at nothing and not saying anything for a long time.
"I died, (Y/N). I'm not sure how you brought me back but, I know I died." Your throat became very dry, you knew Sans had dead, you saw his soul go grey but it didn't shattered. Any second later and he would have been got forever.
"(Y/N)." Sans was looking right at you, unwavering and serious. "How did you bring me back?" You didn't want to answer the question because you knew you did something outrageous. You wanted to look away, youu wanted to run, but you couldn't.
"I-i... I... used m-my... soul..." Your voice was very quiet and cracked like no one's business.
Sans stood straight up, backing up a bit and looked at you like you just said you made a deal with the Satan himself.
"WHAT?! ARE YOU F*CKIN CRAZY?!"
You used all your strength to move back up on the bed.
"No, I didn't know what else to do." You said trying to remind calm.
"F*ckin hell (Y/N), you could have, you could hav-" You snapped.
"LET YOU DIED, FOREVER?!" You cut off Sans with your scream. Tears started to form in your (E/C) eyes. "NO! I'm too damn selfish! I wanted you by my side. I was not going to let another person I love die! I- I- I..." Your voice broke as you were in full on tears. You were trembling all over and could barely breath. Sans walked over to the other side of the bed and pulled you down with him laying you both down carefully.
"Shh~ it's okay. I'm okay. I'm sorry." Sans embraced you and slowly stroked your (H/L)(H/C) hair. You buried yourself into his jacket that smelled like mustard and snow. Your breathing finally calmed down. Even though you've just woken up you were extremely exhausted, you let your eyes relaxed and fell into a dreamless sleep.

Sans POV

She had just woken up and now she is back asleep...
Probably wasn't the best idea to scream at an ill person who f*cked up there body to saved your life...

I tried to get up to tell Paps and everyone (Y/N) woke up to calm their fears, but she held on to my jacket. She pulled herself closer and whispered, "Don't leave me, Sans." I couldn't tell if she was asleep or not but I settled back in to the bed.
I 'kissed' her on the head and whispered back, "I'm not going anywhere." I slowly fall asleep admiring (Y/N)'s beauty.