Undertale x Child!Reader Scenarios

Mommy Issues (Undyne x Baby!Monster!Reader)

You're the child of Alphys and Undyne here! How is that possible, you may ask? Well Alphys IS a master at magical science, I'm sure it wasn't too hard to figure something out.

"Come on, pick up already!" Undyne screamed at her phone.

Alphys' voicemail greeting answered; "Eh, hello, this is the voicemail of D-Dr. Alphys! I'm not here t-t-to answer your call, so um... leave a message?"

The machine beeped, and Undyne shouted, "There's no way you haven't seen all my missed calls! For like, the hundredth time, I need help with the baby!"

She hung up.

You, (Y/n), the baby of which she spoke, sat on top of the fridge giggling at your mother down below. She had tried to coax you down, but your infant brain didn't understand what the problem was. She couldn't reach you, and using her spear would not be the safest option.

"How did you even get up there, you little punk?" She growled. You just stuck your tongue out in response.

Undyne rubbed her temples in frustration. "Okay, okay, let's do this differently..."

She donned the sweetest smile she could muster and held out her arms, saying, "Come to mommy, (Y/n)! Come on down! You can have a cookie if you come down from there... no, two cookies! Just jump into my arms, sweetie!"

You didn't comprehend most of that sentence, but you heard "cookie", which was always a good word, so you crawled to the edge of the fridge top and sat there, babbling.

Undyne jumped up and just barely managed to grab you from the edge. She fumbled with your tiny body for a moment, causing her to fear dropping you, but in the end you were caught in her arms.

The tall fish monster put you in your high chair next to the table so you wouldn't go anywhere, and you proceeded to slap the built-in tray as if performing a little drum solo.

"You wanna be a musician, squirt?" Undyne laughed. "Mettaton could probably give you some lessons! He has always said you can never be too young to build a talent... agh, I'm getting all cheesy now."

You stuck your tongue out again and tugged on your mother's ponytail.

"What?" She grunted.

"Foo!" You squealed. You were hungry now, and you always heard someone saying "food" whenever you got fed, so you assumed that repeating the word would get you lunch.

"You tryin' to say something, little punk?"

"Foo... foob... foob."

Undyne laughed again. "You want food, right? I'll get you some, just gimme a sec—"

"Food! Food! Muh... ma! Food, mama!"

"YOOOOOOOOOOOOOOOOOOOOOOO—"

The front door opened, and Alphys shuffled in.

"H-hey, I'm home! I know I'm late, but m-my phone spontaneously e-exploded, and—"

"BABE!" Undyne screeched from the kitchen. "COME OVER HERE!"

Worried, the scientist rushed over. "W-what's wrong? Did something bad happen?"

"No, something great happened!" Undyne held you up Lion King style in all your squishy baby glory and commanded, "Speak!"

"Speep!" You blabbed, trying to mimic her.

"No no, say what you said before!"

Alphys pushed up her glasses. "(Y/n) talked?!"

"Yeah..." Undyne lowered you a bit, sighing. "But it seems... my power means nothing to an infant."

(I will be shook if someone gets that reference.)

The shorter monster giggled. "You can't make a baby talk just by commanding it! Their brains aren't that developed yet!"

You squirmed around in Undyne's grasp. "Pud... put... put down?"

She lifted you back up and hollered, "YES! OUR CHILD HAS SPOKEN AGAIN!"

"Please put the baby down," Alphys sighed.