Title: The Secret Ingredient
Author: cruisedirector and dementordelta
Other pairings/threesome: Background Ron/Hermione
Rating: NC17
Word count: ~16,500
Content/Warning(s): EWE, not Next Gen-compliant
Prompt: #001: Go Prompt Yourself
Summary: When Gilderoy Lockhart invents a miraculous memory potion, Harry suspects that something else is going on.
A/N: Thanks to torino10154 for beta!

Read on AO3

(The Secret Ingredient)