Love Is in the Air! Scott Disick and Sofia Richie Kiss Aboard Private Plane

 

Scott Disick and Sofia Richie are taking their relationship to new heights.

Ever since they confirmed their romance last month, Sofia, 19, and Disick, 34, haven’t wasted any time packing on the PDA. On Sunday, the two were aboard a private plane together when a pal snapped a photo of the couple holding hands and kissing, which Richie added to her Instagram stories.

The on-camera make-out is just the latest in a string of photos they’ve shared of each other on social media.

Last week, the two heavily documented their trip to Punta Mita, Mexico, while a source told PEOPLE that Sofia has been referring to Disick as “her boyfriend” and “thinks he’s the best.”

RELATED VIDEO: Scott Disick and Sofia Richie Get a Congratulations Dessert and Become Instagram Official

 

The couple first sparked 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, Sofia — who previously dated Justin Bieber — adamantly denied anything romantic was going on, tweeting that the two were “just homies.”

The relationship has raised a few eyebrows, and a source recently told PEOPLE that Sofia’s father Lionel Richie isn’t too pleased about it.

“He thinks Scott is the worst person she could ever see and that he raised her better than that,” said the source of the American Idol judge’s reaction. “He thinks she should have more respect for herself as a young woman. Lionel knows Scott’s playboy ways and he doesn’t want to see his daughter get hurt.”

The insider also said Sofia is “much more invested in the relationship” than Disick, who shares three kids with his ex Kourtney Kardashian, 38.

“Scott isn’t treating this as a long-term relationship whatsoever,” said the source. “He is just having fun. Sofia wanted commitment from him, so he committed to be her ‘boyfriend.’ “

“He still has Kourtney at the top of his mind all the time, and he is still texting and flirting with other girls,” the source added. “Sofia is very young and naive and doesn’t know what she’s in for. She feels like she’s in the in-crowd right now and loves that Scott has swagger and money and that he loves to travel and party.”