High on a Greenpoint rooftop overlooking the East River, Nicole tipped back her third strawberry THC-infused cocktail and snatched a joint out of her friend’s mouth.

“Sharing is caring,” said the 22-year-old graphic design student (who asked that her last name be withheld for professional reasons).

Smoking is only allowed outdoors at the posh, two-story loft where Brooklyn’s newest illicit marijuana party, Spleef, attracted some 100 stylish and trendy locals on April 21.

“It’s to make sure the vibe stays classy,” said Spleef founder Mike, the 32-year-old NYPD Police Academy dropout at the center of the drug-fueled soiree. “Smoking inside makes it feel seedy.”

But there were plenty of other ways to ingest indoors, including bottomless cocktails and hors d’oeuvres, truffles and pastries — all infused with THC (tetrahydrocannabinol), the psychoactive chemical in marijuana.

THC is illegal in New York state, as are the various strains of high-class marijuana — purple punch, lemon sherbet, Mercedes-Benz — that were available for purchase at the Spleef party.

“We’re stripping away the stigma of cannabis and turning it into something elegant,” said Mike, who exclusively spoke to The Post on the condition that his last name be withheld. “But we’re taking a huge risk.”

This was the fourth illegal Spleef “speakeasy” since the events — which cost between $50 to $100 — started in January. They take place in secret locations throughout the city, including in Astoria, Bushwick and the Lower East Side, and the addresses are announced via private e-mails sent after guests purchase tickets through the Spleef Web site.

The ethnically diverse crowd— largely made up of people in their 20s and 30s — was filled with filmmakers, writers, street artists, fashion designers and others.

There were hundreds of ounces of cannabis concentrate — which carries a harsher sentence than possession or distribution of raw marijuana — in both cocktails and for sale in bottles. Had the party been busted, this could have landed Mike and his business partner, Mark, 27, in jail for up to 15 years and a $15,000 fine.

There was also at least half-a-pound of actual marijuana for sale, which could have led to a sentence of up to seven years and a $5,000 fine. (Although Mark and Mike recruited distributors to sell the pot, they could still bear responsibility.)

Had attendees been found in possession of any amount of the THC tincture, they could have faced jail time of up to a year. Although the city has lightened up on smokers, in 2017 nearly 18,000 New Yorkers were arrested for low-level possession.

“That fright still exists,” said guest Ayende, 24. “But this type of gathering makes doing marijuana normal — comfortable.”

And then there’s Mike, the co-host, who until two years ago had never dreamed of touching marijuana. He was raised in a strict Catholic household by Ecuadorean-immigrant parents in University Heights.

“My dad always taught [me and my siblings] that bad kids smoked marijuana — and we were good,” he said. “So we were scared to touch it.”

‘We’re stripping away the stigma of cannabis and turning it into something elegant’ - Mike

After marrying and becoming a father at 21, Mike eventually made his way into the NYPD’s Police Academy in 2015. Two months later, his life was turned upside down.

“Somebody sent in a private text chat that I [had] had years ago with a friend and [in which] I used a word that they thought was inappropriate,” he said. “I was asked to resign.”

He picked up jobs as a personal trainer and applied to the US Border Patrol — but was rejected again.

“I needed to find something else,” said Mike, who is now divorced and in a relationship.

In August 2016, one of his personal training clients gave him a pot lollipop.

“I had no idea what to do with it because I didn’t know anyone who did [marijuana],” Mike said. After offering it to his girlfriend’s sister, she introduced him to Mark, a Queens native who works as an editing assistant at a major television network and began smoking marijuana at 13.

Mark started selling homemade THC brownies when he was a freshman at Brooklyn College — where he was nicknamed Mr. Spleef — and his hobby grew into a full-fledged business. By the time he met Mike in 2016, he was looking for distributors to sell the edibles.

“At that point I thought, ‘F–k it,’ I’m just going to try the stuff,” said Mike. He started with a weed cookie. “I was like, ‘Woahhhhh.’ It was such a great experience. As cheesy as it sounds, it really changed my life.”

Fearing that “the edible market is oversaturated,” Mark said, he and Mike came up with a fresh approach. “We were like, ‘What else screams class? Cocktails.’ ”

Last November, the duo set up their first bar at an underground marijuana convention held in a Harlem brownstone.

“It was a huge success,” said Mark, so they moved on to hosting their own events.

The two craft their illegal Spleef tincture by soaking marijuana in Everclear and adding 10 milliliters of it to cocktails they’ve dubbed White Gold, Love Potion, Spring Garden and Folium Viride.

At the April bash, partygoers imbibed seemingly without fear.

“It’s so well-put-together, they have to know what they’re doing,” said Ayende. “Being here feels like being in Amsterdam. There’s no stigma — it’s just part of the culture.”