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1. if he only knew by Anonymous

   Fandoms: Harry Potter - J. K. Rowling  

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

   22 Nov 2025

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Regulus Black/Sirius Black
   • Sirius Black
   • Regulus Black
   • Dead Dove: Do Not Eat
   • Smut
   • Shameless Smut
   • Incest
   • Sibling Incest
   • Gay Sex
   • Anal Sex
   • Dubious Consent
   • Polyjuice Potion (Harry Potter)
   • Sex While Using Polyjuice Potion (Harry Potter)
   • Dirty Talk
   • Butt Plugs
   • Simultaneous Orgasm
   • Come Eating
   • Revelations
   • Kissing
   • Boys Kissing
   • Moaning
   • Classroom Sex
   • Daddy Kink
   • slight Breeding Kink
   • Stripping
   • Regulus Black is a Tease
   • Sirius Black is So Whipped
   • Blow Jobs
   • begging Sirius Black
   • Regulus Black is sexy
   • Sirius can’t look away
   • Plot What Plot/Porn Without Plot
   • Not Beta Read
   • Voyeurism
   • Exhibitionism
   • exhibitionist Regulus Black

   Summary

   Sirius uses polyjuice potion to pull a prank on James by looking like him. But James has been keeping a secret from him. He’s been secretly sleeping with Regulus, but Sirius finds out about that…when Regulus pulls him into an empty classroom, thinking he is James.

   Sirius tries to leave, he really does, but Regulus‘ lips are way softer than he expected…

   Language:

   English

   Words:

   7,029

   Chapters:

   2/2

   Collections:

   1

   Comments:

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   Kudos:

   254

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