Knives and biting? No... but there is the wonderful, delicious pain of being whipped... and that certianly can draw blood!
I say, go search for a good book about it-
www.stockroom.com is a wonderful site full of BDSM toys and books and is run by industry professionals, so it's all top quality stuff. Don't do it on the $300 white sheets, make sure you both are disease free and such, and keep the first aid kit well stocked so you can patch up afterwards.
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Sage knows our mythic history, King Arthur's and Sir Caradoc's
She answers hard acrostics, has a pretty taste for paradox
She quotes in elegiacs all the crimes of Heliogabalus
In conics she can floor peculiarities parabolous
-C'hi