The young lovebirds eat and party together at Art Basel

By Becky Randel
Updated December 04, 2014 02:45 PM

They may not be the most obvious couple, but Miley Cyrus and Patrick Schwarzenegger’s budding romance was on full display in Miami this week.

They arrived in the Magic City on Tuesday in preparation for the singer’s Art Basel performance. One of their first stops: Dinner at the famed Joe’s Stone Crab. For their date night, they kept things casual, with Cyrus wearing denim shorts, a crop top and a denim jacket while Schwarzenegger wore a Kenzo sweatshirt and dark pants.

While relaxing at the Fontainebleau, the duo were seen “holding hands and being sweet to each other,” a source tells PEOPLE. “They were both extremely low-key.”

The next night, during her big performance at Tommy Hilfiger and Jeffrey Deitch’s V Magazine party at The Raleigh Hotel, the singer cranked up the energy by several notches.

Dressed in a silver leotard, silver pasties and a silver wig, Cyrus sang everything from Johnny Cash to Led Zeppelin to the Beatles – and even lit up a joint on stage.

“Usually I don’t smoke weed and drink. Well, that’s a lie,” she told the crowd. “Usually I don’t smoke and drink on show days, but I felt like it was fine in Miami.” Since she was performing during an art event after all, Cyrus also explained her recent dive into that world.

“There was a year where I did VMAs and I had my first single and it just felt like nothing really meant anything and I wasn’t making music just because I loved it anymore,” she continued. “So then it took a really s––––– thing happening to me – losing my dog – for me to kind of get my perspective again and once I did I started making art.”

Meanwhile, Schwarzenegger watched from the VIP tent where he was partying with friends. He was “rocking out the whole time,” a source tells PEOPLE. After the show, the twosome headed arm-in-arm to the E11even Miami 24-hour show club, where Miley kept the festivities going.

Dressed in a black lace bra top and her silver wig, Cyrus hopped on the stage with the club’s Michael Jackson impersonator to sing a rendition of “Billie Jean” as fellow partygoers – including Leonardo DiCaprio – looked on.

“She’s like Madonna was 20 years ago,” Tommy Hilfiger told PEOPLE of Cyrus. “Madonna was shockingly outrageous but a talent. And I think Miley has all of that plus plus plus.”

With additional reporting by JENNIFER GARCIA