Undertale Tickle Stories (Main Series)

A "Humerus" Sleepover (Chapter 4)

Chapter 4 of this long story. In the first three chapters, Frisk, M.K., and Papyrus tickled the crap out of each other and M.K. and Papyrus used new methods of tickling that surprised the hell out of Frisk. :) In this continuation, the kids have come up with a plan to get revenge on Sans for all of the mischievous pranks he pulled on everyone during the month. For their revenge, they're going to tickle the crap out of Sans! :D 

Undertale© Toby Fox.

A "HUMERUS" SLEEPOVER

Chapter 4: Getting Back at Sans

It is now 8pm and Frisk and M.K. are currently watching movies with Sans and Papyrus in their living room (They started watching movies at around 5:30pm). During dinner, Frisk wondered if Sans was going to do some type of prank with the movies and it turned out she was correct. Sans had put all of them in the wrong cases and it took about fifteen minutes to find the exact movies they wanted to watch. This practical joke only furthered Frisk and M.K.'s desire for revenge and with Sans constantly falling asleep while watching the movies, it's the perfect time to strike. Frisk was about to ask Papyrus if he wanted to help them, but he had received a phone call and Papyrus never rejects phone calls. Papyrus then left the kids alone in the living room with his sleeping brother to talk to whoever was calling him on his phone. Before Papyrus's phone rang, he was planning on leaving the room to grab some snacks.

Sans: *snoring*

Frisk: *whispering to M.K.* Sans keeps falling asleep. This is perfect. You ready M.K.?

M.K.: *whispering to Frisk* You know it Frisk.

The kids then moved closer to Sans so they could get ready to tickle him. Sans is such a heavy sleeper that the kids' sudden movements as they positioned themselves closer didn't even make the lazy skeleton flinch.  

The kids are sitting on the couch right next to Sans. When looking at the couch from the front side, Sans is sitting in an upward position in the middle of the couch with M.K. sitting to the left of him (Sans's right) and Frisk sitting to the right of him (Sans's left).

As soon as Frisk and M.K. were all situated, they then held their hands right next to Sans's ribs.

Frisk: *whispering* 3... 2... 1...

M.K.: Hey Sans, it's time to wake up!

Sans: *still sleeping*

Sans is such a heavy sleeper that M.K.'s yelling wasn't enough to wake him up. Even though M.K. is literally sitting right next to him! Perhaps some tickling will wake him up. ;)

Frisk and M.K. then began tickling Sans's sensitive ribs.

Sans: AHAHAHAHAHAHAHAHAHAAHAHAHAHAHAHAHAHAHAHAHAAHAHHAHAHAHA HAHAHAHAHAHAHAHAHAHAAHAHAHAHAHHAHAHAHAAHAHAHAHAHAHAA!!! WHAHAHAHAHAHAHAHAHAHAHAT THE HEHEHEHEHEHELL ARE YOU KIDS DOHOHOHOOOHOOING?!!!

To Frisk and M.K.'s surprise, Sans immediately woke up and burst into loud, frantic laughter the very moment they touched his ribs. Sans must be pretty damn ticklish if all it took to wake him up was a light touch to his ribs!

Frisk: Well Sans, you keep falling asleep! I figured a few harmless tickles would help keep you awake!

Sans: HAHAHAHAAHHAHAHARMLESS?!!! THIS IS AHAHAHAAHANYTHING BUT HAHAHAHAHAHAHAHARMLESS!!! M.K., AHAHAHAHAHAHAHA DID YOHOHOOOOHHOHOOHOU TELL FRISK THAHAHAAHHAHAHAAHAHAT I'M TIHIHIHIHHIHICKLISH?!!!

M.K.: *lies to Sans* Nope!

M.K. figured it was ok to lie to Sans when he was asked if he told Frisk that he was ticklish because technically, M.K. didn't break Sans's promise. It's just that Frisk was able to read him like a book earlier, so he had no choice but to tell her that Sans is indeed ticklish. And it turns out M.K. was correct! ;)