Asphyxiaphilia is a paraphilia where sexual arousal or orgasm depend on the deprivation of oxygen as a result of self-strangulation or partner induced strangulation. The point, for the asphyxiaphiliac, is to be deprived of oxygen up to, but not including, the point of unconsciousness. It is considered a paraphilia due to the dangers of death by strangulation.
More About Asphyxiaphilia
Asphyxiaphilia is dependent upon autoerotic asphyxiation for sexual arousal. The practice of self-strangulation, usually used for masturbatory purposes, is especially dangerous. If done improperly, it can lead to unconciousness or even death. Partner play is slightly less dangerous, though it is very easy for a partner to slip into unconsciousness. Thus, the practice carries with it some inherent risks that classify it as a sexual paraphilia.