Slash of the HP variety
I've been going through the Restricted Section's archives digging for good RL/SB and femmeslash (I believe I favor LL/GW particularly) and there is a lot of kink in there. While doing so I've been thinking about my requirements for glancing at smutfic.
1. There be no Deatheaters involved. (In my world, Voldemort and his buddies don't get any. If they do, as evidenced by the procreation of Lucius Malfoy and Narcissa, I don't need to hear about it).
2. No incest. Actually, this is a general requirement of mine that I waive only for Greek gods and goddesses and the like. It's canon for them to be shagging each other.
3. No shota. See 2. Sex between minors as long as they're at least sixteenish is okay. Students and teachers is right out.
4. No bloodplay, non-con, violent BDSM. See 3. Games are only fun as long as nobody gets hurt.
Sadly, this cuts out quite a lot of fic right away.