This is from IJ's Daily Deviant Kinky Kristmas Fest, and is one of the hottest things I've read in ages.
Title: Not Too Young
sabetheaCharacters/Pairings: Remus/Sirius/Harry
Rating: NC17
Kinks/Themes Included: Chan, first time, oral, anal, spit-roast
Other Warnings/Content: dirty talk
Word Count: ~3500
Summary/Description: The Weasleys have each other. Remus and Sirius have each other. Harry has no one, and it just isn't fair.
This is set during OotP, so Harry is... 16? It catches Harry's mood from the book very well - angry, frustrated, isolated - and... I can't believe I noticed anything other than the monitor-melting sex, tbh. Oh, my. Sirius and Remus are so bad and Harry is so naughty and... and....
*fans self*
Here's the link.