Belonephilia is a parahilia that hinges on a sexual arousal by or interest in sharp objects. It is classified as a paraphilia due to its potential for bodily harm to the belonephiliac.
Kinkly explains Belonephilia
Belonephilia can include a sexual arousal by or interest in all sharp objects and surfaces. This might include, but is not limited to the use of pins or needles, razor blades, sharp edges, or glass. This particular paraphilia is considered hazardous to the health of the belonephiliac. It may lead to excessive cutting or self mutilation in an effort to gain sexual pleasure. This hazard can also be applied to the belonephiliac's sexual partner. Belonephilia may be related to activities that hinge on sadism and masochism.