Aurelie Corinthios
December 11, 2017 10:59 AM

If you Keep Up with Scott Disick at all, you know that it’s not at all unusual for the self-proclaimed lord to be surrounded by a slew of young models and socialites — but these days, Disick has eyes for one woman only: his 19-year-old girlfriend Sofia Richie.

The two recently made their first public event appearance as a couple at Art Basel in Miami, and despite the pairing initially raising eyebrows, a source tells PEOPLE that Disick, 34, has a certain undeniable appeal.

“Scott has a sarcastic sense of humor that people love to be around — especially women,” the insider says. “Despite his public persona, he can be charming and make you feel like the only person in the room.”

Though they haven’t publicly discussed their relationship, Richie and Disick — who shares three kids with ex Kourtney Kardashian — haven’t been shy about showing it off, packing on the PDA during several Miami outings and beachside tanning sessions.

Scott Disick and Sofia Richie
Andrew Toth/Getty
Scott Disick and Sofia Richie
Romain Maurice/Getty
Scott Disick and Sofia Richie
Alexander Tamargo/Getty Images

The couple first sparked romance speculation in May after they were pictured cuddling up aboard a yacht in the south of France during the Cannes Film Festival. At the time, Richie — who previously dated Justin Bieber — adamantly denied anything romantic was going on, tweeting that the two were “just homies.”

Months later, the two had become “inseparable,” a source told PEOPLE in mid-September. They confirmed their romance shortly afterwards with friends in Miami, capping off the trip with a few days in Mexico. In the months since, the couple have spent much of their time traveling together, enjoying a romantic Italian getaway and another trip to Mexico.

Another source recently told PEOPLE the two are “very serious” and that Richie has been a positive influence on Disick, who has openly struggled with alcohol abuse.

“She’s been great for him,” the source said. “She’s made a big impact on his life and hasn’t partied at all since they met.”

“His friends adore her and nobody notices the age difference,” the source added. “She is very mature, she grew up in Hollywood and has always been in older situations. They seem really happy.”

RELATED VIDEO: Kourtney Kardashian & Scott Disick on Possibly Getting Married at 40

While a source previously told PEOPLE that Richie’s famous father Lionel isn’t too pleased about the relationship — “Lionel knows Scott’s playboy ways, and he doesn’t want to see his daughter get hurt,” the insider said — the model has insisted that her dad is on board.

“He’s good — he’s been very nice,” she told E! News at the SAG-AFTRA Foundation Patron of the Artists Awards in Beverly Hills last month.

“He’s been very cool,”  she added of the singer. “He’s very supportive, whatever that means,” she added as Lionel, 68, jokingly pointed a gun-shaped hand gesture at his head.

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