A video of them together at a restaurant in Paris went viral in July and sparked dating rumours.
Blackpink's Lisa and Frederic Arnault were recently spotted together again, leading netizens to believe that they are really dating.
Arnault is the CEO of Tag Heuer and son of billionaire Bernard Arnault, the CEO of LVMH, a conglomerate specialising in luxury goods, owning brands such as Louis Vuitton and Dior.
The senior Arnault is ranked number one in Forbes Billionaires 2023 list.
Lisa and the younger Arnault were thought to be on vacation together recently.
The 26-year-old Thai pop star posted photos from her holiday on Instagram on Aug 9, which were speculated to be taken in Greece or Italy.
In the same week, Arnault, 28, posted photos of his watch against a similar-looking landscape on his Instagram.
Fans dug deeper and found that his sister-in-law Geraldine Guyot-Arnault had also posted photos in both Greece and Italy recently.
Now, a new undated photo of Lisa and Arnault has been making its round on social media.
The photo was allegedly taken at a private airport in Los Angeles, and shows the two sitting next to each other on a couch.
It is rumoured that Lisa boarded a private jet owned by Arnault in New Jersey, US, after Blackpink's concert at the Metlife Stadium on Aug 11 and 12, and they later flew to Los Angeles together.
The rumours have not been confirmed or denied by both parties.
Fans of Blackpink have flooded the comment section of Arnault's Instagram account, some supportive while others were the opposite.
"I love this couple," one commented.
Another asked Arnault to make the relationship "public".
One fan remarked that "Lisa deserves better".
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