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1. Who Even Has Sex on the First Day of College? by pisswizards

   Fandoms: Invincible (Cartoon 2021)  

   • Explicit
   • No Archive Warnings Apply
   • M/M
   • Complete Work

   07 Jul 2026

   Tags

   • No Archive Warnings Apply
   • Mark Grayson | Invincible/Rex Splode | Rex Sloan
   • William Clockwell & Rex Splode | Rex Sloan
   • William Clockwell & Mark Grayson | Invincible
   • Mark Grayson | Invincible
   • Rex Splode | Rex Sloan
   • William Clockwell
   • Alternate Universe - Canon Divergence
   • College
   • Flirting
   • Kind of some William/Rex but not really
   • William just flirts with him
   • Friends with Benefits
   • Submissive Mark Grayson | Invincible
   • Bottom Mark Grayson | Invincible
   • Top Rex Splode | Rex Sloan
   • Dominant Rex Splode | Rex Sloan
   • Trans Mark Grayson | Invincible
   • Possessive Sex
   • Possessive Behavior
   • Jealousy
   • Jealous Mark Grayson
   • Trans Male Character
   • Vaginal Sex
   • Oral Sex
   • Penis in Vagina Sex
   • Rough Sex
   • overuse of the petname “baby”
   • Makeup Sex
   • Developing Feelings
   • Developing Relationship
   • Mark hiding his romantic feelings for Rex (really badly)
   • Squirting and Vaginal Ejaculation
   • Spanking
   • Hair-pulling
   • Blowjobs
   • Mark Grayson is weak to Rex’s petnames
   • and Everything else
   • Multiple Orgasms
   • Viltrumite DNA mentions (plot relevant to sex)
   • Viltrumite DNA makes Mark’s tdick bigger lol
   • Literal Sleeping Together
   • Teasing
   • Sex in a shitty dorm room bed
   • Doing a really bad job at staying quiet
   • Sock on the door means somebody’s fuckin
   • First day of college sex
   • if you couldn’t guess
   • Breeding Kink
   • breeding mentions
   • because I can’t help myself
   • shoutout to my beta readers
   • This is mostly canon compliant just imagine that Rex and Mark were established fuck buddies with “secret” feelings for each other
   • and that Rex helped him move into his dorm

   Summary

   “Seriously? Who even has sex on the first day of college?”

   “I dunno Mark…lots of people, probably. Us, for example?”

   But with a Markrex twist :3

   Language:

   English

   Words:

   6,608

   Chapters:

   1/1

   Kudos:

   114

   Bookmarks:

   17

   Hits:

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