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1. Captain On Deck by SugarBonBon

   Fandoms: Undertale (Video Game)  

   • Explicit
   • Creator Chose Not To Use Archive Warnings
   • F/M
   • Complete Work

   10 May 2026

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Sans (Undertale)/Reader
   • Sans (Underswap)
   • AFAB | Assigned Female at Birth Reader-Insert
   • Reader-Insert Has a Vagina
   • Loss of Virginity
   • First Time
   • Vaginal Fingering
   • Mutual Masturbation
   • Penetrative Sex
   • Condoms
   • No making of the babies
   • Ecto-Penis (Undertale)
   • Painful Penetration
   • Premarital Sex
   • Gasp how scandalous

   Summary

   After you accepted his marriage proposal, Sans was determined to show you how much he truly loves you: by giving you a new and exciting experience.

   This is a continuation/Side-story of Chapter 9: Your Greatest Treasure from my other fic ''Captain Down Below''

   Series

   • Part 2 of High Sea Adventures

   Language:

   English

   Words:

   3,716

   Chapters:

   1/1

   Comments:

   5

   Kudos:

   38

   Bookmarks:

   3

   Hits:

   786