Does anyone know what SM means?

Sm is short for sadistic masochism, especially in sex. Sm is a special activity that sexual pleasure and pain are linked together, that is, sexual activity that obtains sexual pleasure through pain. SM is a kind of sexual perversion and belongs to one of the important terms of bdsm. Among them, pain includes both physical pain (such as the pain caused by flogging) and mental pain (such as the painful feeling caused by humiliation and domination). Sadism also includes two categories: sadism and masochism. Putting pain on others, you can get your own sexual pleasure, sexual excitement or simple pleasure, which belongs to the former, while accepting pain can get your own satisfaction, which belongs to the latter.

In the past, in some clubs and hotels, there was a one-stop service, and some couples also played.