Algolagnia

Algolagnia (IPA pronunciation: æl gəˈlægniə) (from the Greek άλγος, algos, "pain", and λαγνεία, lagnia, "lust") is a sexual tendency which is defined by deriving sexual pleasure and stimulation from physical pain, particularly involving an erogenous zone.

Most current research suggests it has a fully biological basis, as it is proven that pain, just like sensorial pleasures such as sexual contact and sweet foods, causes the release of endorphins, the chemicals that induce pleasure. Furthermore, studies conducted indicate differences in how the brains of those with algolagnia interpret nerve input.