From Tab.co.uk —

Feeling spontaneous? Pick two of your mates and get on Grouper, a new “social club” that matches you and two of your wingmen or wingwomen with another trio of the opposite sex for a night out on the town.

After launching in New York in the summer of 2011 and expanding into 25 cities across the U.S., Grouper is now in the UK, gaining fans and swift momentum across the different neighbourhoods of London. To date, we have proudly hosted tens of thousands of nights out and hangovers worldwide.