UNDER-FALLS (Gravity Falls + Undertale).

Prologue

SPOILER WARNING!

for Pacifist Route Undertale

and

Up to before Gideon's revenge or whatever that's called, before Weirdmageddon for  Gravity Falls.

(This story takes place in a Gravity Falls/ Undertale Alternate Universe. This means, Dipper and Mabel have  met Bill, but Weirdmageddon hasn't happened yet... however, Ford is in this, a little bit.. well, you'll see what happens. Mabel and  Dipper are... mm... probably fifteen-sixteen in this, so have matured a bit, but will still keep many of their childish ways, don't worry.)

Hey there, reader!

My name is  Mabel Pines.

Would you care for a story?

...One that's.. rather long?

One that can be changed, shifted, re imagined?

Good.

Because have I got a tale to tell you...

...

An 

UNDERTALE.

I woke up, smiling at the clock, and then chuckled softly, seeing Dipper wrapped up in his blankets, sprawled out on the floor, his books and pens were scattered across his bed, and he was probably too tired to clean up, before passing out.

It made me smile.

"Oh, Dipper. You Nerd."

I poked him, gingerly.

He didn't wake up.

I gave him a soft punch.

He simply stirred,

I rolled my eyes, leaned close to his ear, and...

"Dipper!" I screeched, and he startled awake, jumping practically out of his skin.

"Ah!"

"C'mon. It's really nice out, there's some cloud-cover, we could go check out the Mountain."

"B-but I just figured out-"

"No, 'but's' Dippy-Dip, you need fresh air. I refuse to let my brother become a hermit."

"If anyone's a crab, it's you!"

I chuckled.

We grabbed our backpacks, mine containing my scrapbook, notepad, camera, walkie-talkie, and cellphone, while Dipper's had his Journal in it, some Nerd stuff I still didn't understand, and a walkie-talkie.

I, had chosen a Photography and Journalism course to follow, while Dipper had chosen something about ...math? maybe?

Dipper followed me out the door, and I ran down the wooden steps, off the porch, and across the field, I stepped into the forest, and glanced back, making sure Dipping dot was following me,  which he was.

Somehow, I'd become more athletic than him.

not surpising.

"Is it just me.. or does it look like there's a path.. and... a cave.. up there?"

"...I see it too." I said.

"Race you to the top!"

He yelled, and I bolted forward, laughing,

I had missed games like these.

I beat him, and I was grinning,

"Mabel wins! Victory screech! Awooooooo!"

"Ah-har-dee-har-har, you're just rubbing in my face the fact that while I beat you in brains you beat me in heart."

"And I'm never gonna stop!"

"Heheh, I don't expect you to."

"Hey, Dip-stick, what's that?"

He looks over to what I'm pointing at, where the floor gives way to a gorge.

"Don't fall in.. it... looks pretty deep."

I took a photo of him, standing beside the gorge, and put away my camera.

"Ha, Do you really think I'm stupid enough to-"

I slipped.

He caught me, before I fell in, but he was... not.. the strongest... in the world.

Dipper tried to pull me up, as I clawed my way up with my other hand.

"Dipper! Do something!"

"I'm trying!"

It almost felt like something grabbed my leg.

I lost my grip on the ledge,

and suddenly

We fell in,

both tumbling, I reached for his hand, caught it.

We hit the ground.