Thongs and frosé? It’s a selfie-centered crowd at Vesper Dayclub, NoLibs’ 21+ swimming pool

As my eyes adjust to the dazzle of sunlight flashing off the inviting aqua rectangle at the heart of Vesper Dayclub, I spy a swimming pool scene that David Hockney never imagined.

A lithe, shirtless man in his 20s is unashamedly mounting a slippery float in the shape of an eggplant emoji. A couple, more making out than kissing, is squeezed together into the hole of a doughnut float built for one. And, everywhere I look, there's a spectacular array of pool-wear: see-through lace pants, dresses constructed seemingly out of loose bits of string, vanishingly tiny thong contraptions, a men's tank top simply reading "Daddy."

But perhaps most notable are the selfies — the duck-face, fish-gape, high angle, professional-grade selfies. At one glorious moment, as the sun slides toward the horizon, I glance around the club and find three selfies being taken at once.

This figures: Vesper Dayclub is, above all, a space designed for and populated by Instagrammers, as signaled by the membership application, which demands a "clear and recent picture of your face," and links to your Facebook, Instagram and LinkedIn for you to even be considered.

So far, there are 7,000 members, out of 20,000 applicants. "People don't necessarily get rejected," marketing director Manny Romano tells me — but some do get processed faster than others.

My own application, submitted a week ago, has not yet been approved. So, I stop by during an open-to-the-public event, a fund-raiser for PAWS, and find patrons chilling on lounge chairs in a shallow stretch of the pool, sprawled on day beds reserved for bottle service, or dancing perilously close to the pool's edge. (By the end of the day, I will also see a man fall, fully clothed, into the 4-foot-deep pool — wallet, cell phone, cocktail and all.)

This is the fourth reboot in eight years for a compact Northern Liberties space that has caused a great deal of angst for those who attempted to make it into a destination: federal lawsuits, canceled promotions, and a series of new managers who slashed membership costs from $1,000 for the season to $350 to today's right-priced free membership model. ("It's almost like a freemium model — you pay for what you use," Romano says, describing pretty much how every other bar in the city functions.) The current owners, according to Romano, are a group of guys who worked for larger, splashier hospitality ventures such as Harrah's Pool and HQ Beach Club before striking out with their own brand: taking over Center City's Vesper Sporting Club, adding the Dayclub and, this fall, expanding to a new Vesper Sporting Club location just next door.

The new vision of the space is meant to be a cross between Miami and Vegas, though it may be a little more A.C. than anything else.

The best-seller here is frosé. Extruded from a slushie machine, it's pleasantly sweet and refreshing, even though it does not taste as if it actually contains wine. I ask Romano what type of rosé is used. "We're not putting Dom Pérignon in there," he assures me, but does not get specific.

For Dom, you'll have to rent a cabana, day bed or poolside table, where there are set minimums of anywhere from $150 to $2,500 for the day, depending on what space you reserve and whether it's a weekend. These are served by a flock of size-zero 22-year-olds in frugal, white string bikinis, darting quietly through the space until — BAM! — someone orders $250 worth of Ketel One or a $795 bottle of Dom Pérignon Rosé. Then, they set off a startlingly loud airhorn siren and dance over to the spendy table in question, holding aloft the bottle and a series of giant cards, as if counting off rounds of a wrestling match.

The reason for this demonstration I can't intuit — but I have a guess. I bet it looks amazing on Instagram.

Vesper Dayclub

1031 Germantown Ave., Philadelphia, 267-713-8987, vesperdayclub.com

When to go: Those days when you just can't deal with going to the office. It's open 11 a.m.-7 p.m. daily, weather permitting.

Bring: Anyone you don't mind seeing in a bathing suit. (Whatever you do, don't bring your kids — this pool is 21-plus.)

What to order: Stick to the frosé (it's $12 a cup — or "make it a mason" and get double the serving for $20). Or, opt for a can of beer, preferably drinking enough that you no longer mind paying $7 for a Yuengling. Skip the house cocktails, which are made with top-shelf liquor but, unfortunately, are not mixed at all — making delicious-sounding offerings such as the Balboa's Basil (Tanqueray, Saint Germain, basil and cucumber syrup for $13) surprisingly undrinkable.

Bathroom situation: A large, multi-stall space with chandeliers, lots of subway tile and, OK, maybe a little vomit on the floor by the end of the evening.

Sounds like: A DJ on duty spinning 50 Cent, Ed Sheeran and Major Lazer hits close to 100 decibels — loud enough to make conversation difficult, but not impossible.