"The dress code is strictly enforced, " says 'Fig', one of the organisers of the event which takes place in Dublin next Saturday night. "The range of outfits allowed are fetish, leather, cyber, gothic, fetish drag, corsetry, burlesque, high formal (top hat and tails) historical fetish, roleplay and lingerie. Getting past the door can be one of the biggest hurdles for new people."

Since it began two years ago, Nimhneach (meaning 'painful' or 'sore' in Irish) has offered ever-increasing numbers of people a chance to act on fantasies which would normally be confined to the bedroom. They are free to take part in 'scenes' in Dublin's Voodoo Lounge, where people engage in BDSM (Bondage, Discipline, Sadism and Masochism) activities such as whipping or flogging.

"People bring their own whips and floggers but rope is provided, " said Fig. "We have some dungeon equipment, including a spanking bench, hanging handcuffs and a double A-frame [a wooden structure to which people can be tied]."

However, some are content just to watch rather than take part.

"Some people will just enjoy being dressed a particular way so the whole thing is engaging in their fetish for them, " says David (31) from Dublin, who regularly attends Nimhneach.

"The biggest parts of most scenes for most people goes on in the mind, and sometimes you don't need to get physical, so two or more people having a conversation could be getting into something pretty intense."

David, who has attended about six Nimhneach events, found there was little awkwardness among those who go along.

"I wasn't particularly nervous the first time I went, but my girlfriend was. However once you overcome any nerves you might have, I'd say it's slightly easier to interact with other people than in most other social situations.

"There's a degree of barrierbreaking just being in fetish gear that's partly because a lot of people are getting to express a side of themselves that they keep locked up."

The average age of those in attendance is about 30, and there is a mixture of couples, groups of friends and individuals.

"As we get quite a number of new people at each event, we have a meeter and greeter whose job it is to say hello to anyone new, " says Fig.

Safety is a concern for organisers. "We don't allow sex on the premises. Nimhneach-ers are all adults and are able to take their own precautions, " says Fig. "We also have dungeon monitors who look in on any scenes that are happening to ensure that they are safe and consensual."

"It can be good fun just to go for a cigarette with my girlfriend tagging along on a chain, " says David. "You do get an interesting reaction walking through the venue with a slave."