by neorenamon

UNDERTALE was created by Toby Fox and all due credit remains with them.

This story includes bondage, milking and oral sex. It is a strange story and should only be read at your own risk. Thank you.

In order to maintain the story as presented, Frisk is still androgynous in spite of turning 16. It's not like Toriel ever bothered to check. Therefore, Frisk will be referred to in gender neutral terms.

...

8 years ago

...

Firsk wanted to get out of the ruins, compelled by some strange urge to discover the truth. But Momma Toriel stood before the gates leading out. She stared down on the child with grim determination.

"If you want to leave here, human," she said, "You have to prove you're strong enough to get by me."

She stood defensively as if she expected her own adopted child was going to attack her, but Frisk turned away and walked back to the house.

"You're such a good child," she sighed as she walked after, "There's your favorite Butterscotch-Cinnamon Pie waiting for you back in your room."

It would be on the floor for some reason. Perhaps monsters didn't have problems eating off the floor or worried about crawling things getting into their food.

...

The night prior to Frisk's sixteenth birthday

...

Toriel awoke from a strange dream. She celebrated Frisk's birthday early and got a little too drunk for her own good. So the child helped her get to bed and assisted getting monster momma undressed. Then the human put her in bed with a soft kiss to her cheek.

But when she was fully awakened, she realized something was very wrong. She had a mild hangover for one. The other thing was that she was not only naked, but hogtied down to her own bed. Her arms were bound over her head, and her legs tied crosswise so she couldn't close them. A thick cloth gag in her mouth kept her almost silent. With her motherly breasts and her loins fully exposed, she felt quite vulnerable.

Then she realized she wasn't alone in the room. The child was still there. Frisk was hardly a child anymore... at least by monster standards... but Toriel couldn't help thinking of the human as a child still.

'Child!' she thought, 'What are you doing to me?!'

Frisk climbed onto the side of the bed as they stroked the side of her cheek softly. Then the human cupped one of her breasts in hand and began caressing it from the base up to her large nipple. The other hand likewise engaged her other breast.

'Oh,' she moaned into the gag, 'That feels so good.'

Then the human surprised her by taking one of her nipples into their mouth. They suckled on it like they were still nursing. There was squirts of milk into the human's mouth with each suck.

'The child knows,' she thought as her breathing sped up, 'My breasts are always making milk. It's the secret ingredient to my Butterscotch-Cinnamon Pie.' She wondered if the child had ever seen her milking herself to relieve the pressure before, or just might have guessed at the milky treasure her motherly breasts contained.

Frisk half crawled onto their adoptive mother as more nipple was drawn into their mouth. She could tell in spite of the low light that the human was still fully dressed with their day clothes.

'AH! Nursing like this always makes me so horny! It's driving me crazy!'

Frisk kept sucking as her milk diminished, but her nipple continued to grow harder.

"Mmm..." moaned Toriel into the gag.

By the time she felt her one breast drained, Frisk switched to suckling on the other nipple. Her fingers stroked and caressed the rock hard nipple making the teasing even stronger.

'UGH! I think I'm going to cum soon! It's just too much!'

Toriel was so excited that even her jerking movements made the ropes strain to keep her tied down. But Frisk used so much rope on her that her chances of breaking loose were all but nil.

'Oh child... it's been so long... So long since I've nursed anyone... So long since I've felt so good about by breasts...'

By the time the second breast was nearly drained, she climaxed strongly. Her back arched as her orgasm swept up and down her spine like an electric shock.

"Mmmmm!" she moaned.

Frisk pulled back from momma as she calmed down. Toriel watched suspiciously as the human moved to the end of the bed.

'Ohhhhhh... What are you planning now child?'

She could feel the human's fingers rubbing up and down her dripping wet cunt. When they came up, she could see her juices dripping off them onto her crotch. She was amazed at just how wet her pussy was.

Then Frisk leaned down and Toriel could feel the human's tongue working her netherlips from bottom to top over and over. The tongue was adept at probing her outer labia.

'Oh child,' she thought as she felt herself getting aroused all over again, 'Why did you wait so long for this?!'

Frisk's arms wrapped about Toriel's thighs as the tongue burrowed deeper into her pussy. The licks came faster and faster as she got hornier all over again. She threw her head back as she prepared herself for another powerful orgasm to sweep over her body.

'UGH! I can't take much more of this!'

By now, Frisk's licks were up to her clit sheath. The tongue lapped up until it was stroking her clit as it came forth. It didn't feel like very long until monster momma's clit was fully erect as well.

'Please child! Don't make me wait!'

Yet Frisk licked her pussy and licked it until she did cum again. This climax felt twice as powerful as the first. Several minutes passed until the stopped cuming, as all they while Frisk kept licking her pussy. She struggled to breathe as she was limited to her nose. Then several more minutes passed as she came down.

'What are you planning to do to me now?'

Her blood ran cold as a knife appeared in Frisk's hand. It was held rather menacingly near Toriel's face.

'Please! It can't end like this! It can't!'

She was greatly relieved when the knife was placed somewhere over her head. It had to be somewhere close to where her hands were bound together. Then the child placed a note on her chest so that it was propped her by her motherly breasts.

'What's this?!'

She began reading the note even as Frisk walked away. With her breasts in the way, she only caught a glimpse of the door opening and then closing. There was just enough light to read the note.

Dear Momma,

I know you've only looked out for my best interests, but it's time for me to go out and discover the truth for myself. It's not possible for me to stay here forever no matter how much you matter to me.

As much as I wanted to leave, I couldn't force myself to attack you! I can't! I won't!

In a few hours, you should be able to reach the knife I left by your hands and cut yourself free. I'll be long gone by then, so don't bother looking.

Once I've found out what the truth is... and I'm still alive, I'll come back and tell you all about my journey. Some day, I'll be back for Butterscotch-Cinnamon Pie, so don't do anything rash until then.

Yes, I know what the secret ingredient is in Momma Toriel's pies. What you meant when you said your pies were full of your motherly love. It just makes each slice all the more special to me.

You've been alone for all the years you raised me, so I had to give you some satisfaction before I go. If anyone deserves this, it's my Toriel Momma.

Don't lose too much sleep over this. I swear I'll make it up to you when I return.

Love Forever,

Frisk.