The duo enjoyed a meal on the rooftop of the apartment on Monday, June 11.
Of the dinner party, which lasted for a few hours, an insider said, "They were eating and drinking and looking at the view and taking selfies".
After ending their meal, the group headed back inside the 27-year-old actress' apartment. It was around midnight when Justin, 46, was caught leaving the apartment with his new dog Kuma, whom he introduced to his Instagram fan followers just days earlier.
This star-studded dinner comes days after the news broke that just one night after Justin and Emma attended the Louis Vuitton 2019 Cruise runway show, they were spotted hanging out and enjoying a romantic vacation together in the south of France.
The duo, who will be starred together in the upcoming Netflix series Maniac, was photographed at the Hotel du Cap-Eden Rock as they relaxed on the patio of a house in the small village of Saint-Paul-de-Vence.
They didn't show any PDA at the time moment but their closeness and comfort to each other, heated up their romance rumors. Earlier, Justin slammed the romance rumors as he shared a photo of them, writing, "Bffffffs. And yes. JUST bfffffs."
In May, the two attended and leave the Met Gala 2018 afterparty together after which the duo's dating rumors heated up.