Adult Content Warning

This work could have adult content. If you continue, you have agreed that you are willing to see such content.

• Yes, Continue
• No, Go Back

If you accept cookies from our site and you choose "Yes, Continue", you will not be asked again during this session (that is, until you close your browser). If you log in you can store your preference and never be asked again.

1. Mix up at the Lab by ShadowMelter

   Fandoms: Undertale (Video Game)  

   • Explicit
   • Creator Chose Not To Use Archive Warnings
   • M/M
   • Work in Progress

   18 May 2016

   Tags

   • Creator Chose Not To Use Archive Warnings
   • W. D. Gaster/Sans
   • Sans (Undertale)
   • W. D. Gaster
   • Asgore Dreemurr
   • Alphys (Undertale)
   • Papyrus (Undertale)
   • Undyne (Undertale)
   • Mating Cycles/In Heat
   • Skeleton Heat
   • Light Bondage
   • Drugs
   • Dubious Consent
   • Soul Sex
   • Gaster is kind of a jerk
   • Sensual Play
   • Touching
   • Sanster
   • Science!Sans - Freeform
   • Ecto-Tongue
   • Non-Consensual
   • Sexual Coercion
   • Angst
   • Hurt/Comfort
   • Drug Addiction
   • Age Difference
   • Height Kink
   • implied past Kingdings

   Summary

   Sans accidentally ingests the wrong experimental drug and things get a bit heated. Doctor Gaster is trying his best to remain in control, but he's not about to let his assistant suffer. However, Sans might be the least of Gaster's worries.

   Language:

   English

   Words:

   34,199

   Chapters:

   12/?

   Comments:

   185

   Kudos:

   900

   Bookmarks:

   63

   Hits:

   19,278