Married At First Sight's Elizabeth Sobinoff and Seb Guilhaus look to be going strong.

The 'intruder couple' showed off their figures in party attire, while catching up with former MAFS star Tamara Joy at the Ultra Music Festival in Sydney on Saturday.  

Lizzie, 29, showed off her slim figure in a plunging black bodysuit with sandals, while Seb, 30, revealed his bulging biceps in a black tank and light blue jeans. 

Tamara, 30, shared a photo from the festival to Instagram, and joked in the caption how it was 'awkward' for herself and Seb to run into Lizzie and former MAFS New Zealand star Samuel Levi.

The Melbourne-based influencer, who had a short-lived 'marriage' with Dan Webb on the 2018 season, turned heads in a skin-tight white frock and pristine sneakers.

She styled her long locks in glamorous curls and enhanced her striking facial features with an immaculate makeup palette.

Tamara stood next to Seb for the photo, and embraced Lizzie, who teamed her festival look with a baker boy cap, drop earrings and straight brunette tresses. 

Lizzie also drew attention to a dark tan, false lashes and a glossy nude lip.

Her 'wedding' to former footy player Seb was filmed late last year, and aired during Monday night's episode. 

The pair appeared to be a great match, with Seb immediately smitten as he watched his bride walk towards him. 

'I am absolutely blown away. My dream girl has just walked up the aisle! I can't stop smiling,' Seb confessed.

And he made a good first impression on Lizzie too, who admitted she was unsure about returning to the show following a disastrous match with Sam Ball, 27, last year.

'He seems lovely. He is handsome and, just, you know, nice smile as well,' she said of Seb.    

After carrying out a series of breathing exercises in an attempt to keep himself calm, Seb prompted a laughing Lizzie to quip, 'We'll get along just fine.'

The sparks continued to fly at the wedding reception, with Lizzie and Seb bonding over their love of silly dancing.