Alright, this challenge is called The "Quidditch Innuendo" Challenge. In this you must have a fic centered around two characters, whether of straight pairing or m/m slash pairing. Also at least one Quidditch Innuendo, sexual in nature, must be present in the fic, though you are free to have as many as you want.
Pairings I enjoy, but you are not limited to, are: teen!James/teen!Sirius, teen!James/teen!Remus, teen!Sirius/teen!James, teen!Sirius/teen Remus, teen!James/teen!Sirius/teen!Remus, Harry/Draco, Fred/George, Bill/Charlie, Oliver/Flint, Oliver/Percy, teen!Sirius/teen!Severus, teen!James/teen!Severus, teen!Remus/teen!Severus, Remus/Hermione, Sirius/Hermione, Draco/Hermione.
I can't wait to see the fics, and I'm sure they'll be great. This challenge will be crossposted in a lot of HP fanfic communities.