Vatsyayana seems to have been a big fan of biting and scratching.

Scratching and Biting
Vatsyayana remarks "nothing tends to increase love so much as the effects of marking with the nails and biting"

The Kama Sutra gives some tips on scratching and biting etiquette.

* Scratching and biting is only for those who find it pleasurable.

* Marks of passion on a woman's breast or throat served to tell the world she is spoken for.

* These marks are not necessary on a married woman, although it is acceptable for a married woman to have them on her private parts.

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