The South African model was ranked among FHM magazine's 100 sexiest women in the world.
Arjun and Gabriella have been holidaying through Europe and sharing pictures on their social media, but this is the first time the couple posted a picture, giving us a clear hint of their relationship.
'All I want for Christmas is,' Gabriella wrote against this photograph.
Looks like a perfect Christmas gift to wish for!Photographs: Kind courtesy Gabriella Demetriades/Instagram
While some of you were busy making New Year plans, Gabriella Demetriades just made it official that Arjun Rampal is taken.
Sharing a picture with the National award winning actor, the 31-year-old model captioned it: All I want for Christmas is...
Scroll down to find out more about Gabriella:
Gabriella is from Port Elizabeth, South Africa. Her parents Kyriacos Demetriades is a businessman and Kia, an artist. Her brother Agisilaos is also an entrepreneur.
'My man crush every day' she wrote about this picture of Arjun Rampal.
A fitness freak, she is seen here doing a headstand in Rishikesh, Uttarakhand.
Posing with fellow models Diva Dhawan and Lisa Haydon.
Guess what? She models for HRX, Hrithik Roshan's athleisure label.
Flaunting her fit frame in a bandeaux bikini.
The Miss IPL Bollywood has also worked films including a cameo in the Hindi film Sonali Cable and the Telugu Oopiri.
In 2010, she was ranked 6th in FHM's list of 100 sexiest women in the world.