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1. Under Their Tails by TebTebmylittlepony

   Fandoms: Undertale (Video Game), Undertale Yellow (Master Sword Video Game)  

   • Explicit
   • Underage Sex
   • F/M, M/M, Multi
   • Work in Progress

   20 Oct 2025

   Tags

   • Underage Sex
   • Other Relationship Tags to Be Added
   • Chara/Asriel Dreemurr
   • Other Undertale Characters
   • Asriel Dreemurr
   • Chara (Undertale)
   • Toriel (Undertale)
   • Asgore Dreemurr
   • Other Character Tags to Be Added
   • Thicc Asriel - Character
   • Shameless Smut
   • Hung Shota
   • Creampie
   • Plot What Plot/Porn Without Plot
   • Good Chara (Undertale)
   • Cause It's Not Actually Them
   • Chara (Undertale) Has Their Own Body
   • Asriel Dreemurr and Chara are NOT Siblings
   • musk
   • Isekai and Transmigration
   • Other Additional Tags to Be Added
   • Large Ass
   • Soul Bond
   • Somnophilia
   • Mildly Dubious Consent
   • Consensual Underage Sex
   • (eventually) - Freeform
   • Shotacon
   • Come Inflation
   • Mating Press
   • Mind Break
   • Anal Sex
   • Scent Kink
   • Submissive Character
   • Cock Worship
   • Rough Oral Sex
   • Rough Kissing
   • Rough Sex
   • Praise Kink
   • Come Swallowing
   • Come Marking
   • Coming Untouched
   • Coming In Pants
   • Underage Kissing
   • Boys Kissing
   • Sloppy Makeouts

   Summary

   Brought to life again as a big dicked version of The First Human in one of his favorite games, James will make sure his perviness and loving warmth will allow him to get with these strangely lewded up characters, while also making sure not to make the same mistake the original did.

   After all, why would he want to leave this Underground?

   Notice: First chapter is more of a notice for people that are interested in this fic before I make an actual chapter, if you don't click on it or do and decide this isn't for you, then all I can say is I hope you have a nice day.

   Though I'd highly recommend you do so i can clear some stuff up for this fic

   Language:

   English

   Words:

   3,884

   Chapters:

   2/?

   Comments:

   8

   Kudos:

   19

   Bookmarks:

   5

   Hits:

   937