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1. inéluctable by pururiru

   Fandoms: Undertale (Video Game)  

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

   06 May 2026

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Sans/Sans (Undertale)
   • Sans Ensemble (Undertale)
   • Sans (Undertale)
   • Alternate Universe - Undertale Multiverse | UTMV (Undertale)
   • Bad Sanses | Nightmare's Gang (Undertale)
   • Something New Sans | Killer/XTale Sans | Cross (Undertale)
   • Something New Sans | Killer (Undertale)
   • Xtale Sans | Cross (Undertale)
   • Dreamtale Nightmare Sans/XTale Sans | Cross (Undertale)
   • Breeding Kink
   • Condoms
   • Creampie
   • Other Additional Tags to Be Added
   • Dreamtale Nightmare Sans/Something New Sans | Killer/XTale Sans | Cross (Undertale)
   • Dirty Talk
   • Knotting
   • Ecto-Vagina (Undertale)
   • Ecto-Penis (Undertale)

   Summary

   His legs locked tight around Cross’s waist, heels digging hard into the sensitive bones of his spine.

   That was when the condom tore.

   The sudden raw slide of Killer’s scorching, velvet-soft walls nearly made Cross’s soul stutter. He opened his mouth to warn him. “Killer, hey—” but only a broken, desperate moan came out, the words garbled and lost as Killer pulled him in deeper and clenched down impossibly tighter. Killer felt too fucking good. Hot. Tight. Perfect.

   Fuck. Fuck.

   Language:

   English

   Words:

   2,439

   Chapters:

   1/1

   Comments:

   7

   Kudos:

   130

   Bookmarks:

   13

   Hits:

   1,071