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1. Sweet Dreemurrs by thatgayguyfr

   Fandoms: Undertale (Video Game), Deltarune (Video Game)  

   • Explicit
   • Underage Sex
   • M/M
   • Work in Progress

   17 Feb 2026

   Tags

   • Underage Sex
   • Asriel Dreemurr/Reader
   • Asriel Dreemurr/You
   • Asriel Dreemurr
   • Reader
   • Male Reader-Insert
   • Cis Male Reader-Insert
   • AMAB | Assigned Male at Birth Reader-Insert
   • Gay
   • Somnophilia
   • Adopted Sibling Relationship
   • Incest
   • Brother/Brother Incest
   • Dead Dove: Do Not Eat
   • Mildly Dubious Consent
   • Consensual Underage Sex
   • Gay Sex
   • Anal Sex
   • Reader-Insert
   • No Use of Y/N for Reader-Insert
   • Drugged Sex
   • Is it as bad as it sounds or am I just a freak?
   • Sleeping Pills
   • Not Beta Read
   • Smut
   • Plot What Plot/Porn Without Plot
   • Perversion
   • Top Reader-Insert
   • Pie
   • Nude Photos
   • Hometown (Deltarune)
   • Sex Toys
   • First Time
   • Blow Jobs
   • First Time Blow Jobs
   • Dubiously Consensual Blow Jobs
   • Scent Kink
   • Anal
   • Anal Plug
   • Fur
   • Furry
   • Brothers

   Summary

   You discover that your older brother, Asriel, has been taking advantage of you in your sleep, and decide to return the favor.

   (Neither person asks for consent but you can be certain they're both into it.)

   Story takes place in the Deltarune universe but I tagged Undertale as well for the hell of it. Might continue this if I have another idea but it works decently as a one-shot.

   Language:

   English

   Words:

   3,065

   Chapters:

   1/?

   Kudos:

   11

   Bookmarks:

   3

   Hits:

   271