Male reader x UNDERTALE [FINISHED]

Chapter 28: Bringing life back in the past

I sat in silence as I stared at gaster.

Y/n: Sharing my soul? What do you mean?

Gaster: I don't possess a soul anymore, but if I had one, I'd be able to go in the past.

Y/n: What about the 'if You survive' part?

He stayed silent for some time before approaching me.

Gaster: The process could definitely damage your soul, and I won't be able to repair it. I need to be sure that you're ready for whatever comes as a result...

I sighed. I need to share my soul with him for us to go in the past to repair my mistake but if the whole soul sharing process fail....

Y/n: Is there an other solution?

He sadly shook his head no.

Gaster: I knew you'd come so I thought about any possibilities whole waiting for you but.... There's no other choice.

I pondered for a bit as to be sure if there wasn't an other solution....sadly, I couldn't think of anything.
I sighed once again as I stand up.

Y/n: Well, gaster, It's whenever you are ready.

Gaster nodded as he looked like he was making hand signs.

Gaster: Then, prepare for pain.

He shot his hands toward me as I could see my soul being ripped apart from me.
I started to yell as the pain I was enduring got worse, the soul came loose as gaster took it in his hands.

Gaster: You possess such a strong soul....

He grabbed each sides and started to infuse something in it as it became darker and darker.
He started to pull each sides apart to break it, or that's what it looked like for me. But I was going through immense pain and didn't have enough grip on what was happening. I just wanted to end it, it was so much worse than I first thought it will be.

I started to bleed just from the sheer pain, my vascular system was running wild as I was about to loose counciousnes for good and probably die.

But I didn't. The pain stoped all at once.
I panted and looked back in front of me.
Gaster had a triumphant look on his face.....

Gaster: It worked!

Y/n: N-nice...

I sat back down as I was somehow exhausted.

Y/n: What now?

He held the two-piece of my soul, it had a weird indescriptible colour.

Gaster: I need to do some tests on it first, to confirm that I will be able to fuse with it.

Y/n: And when w-

He just disapeared. I was now alone in this room, in an other dimension...
Do I just have to wait ...

I got up and looked around again, there was nothing weird or out of place, the only thing that was bugging me was that whole soul test procedures... What he was doing right now was a mystery.

Gaster: Ok, it might really work!

He reapeared in front of me with the same pieces of soul. Nothing had changed but I guess it's not worth minding it.

Gaster: I'll give you half of your soul and I'll take the other, once we have fused with those pieces, there's no going back. I'll transport us in the past to destroy Chara and what will happen next is not something I know. We'll go in blind!

Y/n: There's no other choice.... So let's do it I guess.

Gaster: Well, on the count of 3.

Gaster: 1...

He approached the two pieces near himself and me, each halves to each others.

Gaster: 2.......

He trusted the pieces inside of us, it was like an electrical shock as we both started to shake uncontrollably, we were in a lot of pain.

Gaster: 3!!!!

There was a blinding white flash as I fell uncouncious.

I slowly opened my eyes, feeling numb, and realized I was back in my room, as if nothing happened.

I got up and looked through the window, the town was in perfect shape, nothing had happened.... Or I was back in the past, before Chara's reapearence.

I decided to head out of my room but when I turned around, I saw gaster just in front of me. I stepped back, surprised.

Y/n: H-hey, It worked!

Gaster: Yes.... But Chara Is supposed to break the games codes this afternoon. But since I made us go back in the past, I can't predict if it's gonna go the same way as when you died.

Y/n: Hmm ... So she might come sooner?

Gaster: Yes, but maybe later, who knows

Y/n: For now,we should inform everyone of what might happen soon.

He simply chuckled and looked at me with a grin.

Gaster: How are they supposed to believe us? You think that telling them that you died, then me, a monster sealed in the void a long time ago, made us go back in the past to defeat Chara Is something that they will believe?

Y/n: ....True.... Then what? How should w-

The door of my room opened, it was Sans.

Sans: Y/n, has something ha-

He saw gaster and his eyes went wide.
One of his eyes turned blue as he went serious and used his telekinesis to lift gaster off the ground.

Sans: What the hell are you doing here???

Y/n: Sans! Wait a second I can explain!!!

He quickly looked at me dead in the eyes before letting go of gaster. He just chuckled deeply at Sans' attitude.

Sans: Go on then...

Y/n: Basically, this afternoon, I'll go on a walk to the mountain but a chunk of it disappears, I rush back to the town to see it ablaze and everyone dead. Then Chara kills me, I'm sent in the void, Gaster makes us go back in the past and here we are.

He stayed silent.

Y/n: And he took half of my soul to get us here.

His eyes widened again

Sans: You what??

A/n: Damn, maybe one day I'll have a real schedule XD. Anyway, this second part of the story will be kind of short and we are already almost at the end.
Hope you liked it, see ya!