These Reddit users – of the subreddit "Ask Gay Men" – are talking about poppers, alkyl nitrite inhalants that many gay men sniff from little bottles in order to feel euphoric on the dance floor.
Poppers — the slang term for chemical substances that have long been used by gay men to enhance sex — have found themselves a topic of conversation lately. Not only did we recently discover they were used by one particularly famous TV star, but Australia has long been on a rampage to ban them.
In the '90s, poppers were used in the growing gay rave scene. Now, however, poppers have become more popularized, and some straight people use poppers recreationally (not for sex) at.
Poppers are popular among gays because they relax the sphincter (the anal muscle), give users a moderate-high, and increase sexual pleasure. However, there are dangers associated with the misuse of poppers.