Daniella Hirst and Craig Smith were caught on CCTV engaging in a sex act and having sex in the Domino’s Pizza, on Castle Road, in Scarborough.
They are expected to be sentenced at Scarborough Magistrates’ Court on Tuesday afternoon.
Hirst, 29, of Gypsey Road, Bridlington, pleaded guilty to outraging public decency at a hearing last month.
Smith, 31, of Field Road, Bridlington, was found guilty of the same offence after a 30-minute trial, which was held in his absence while he was in prison in relation to other matters.
Magistrates at the trial watched the 18-minute footage showing the pair in the pizza shop in February.
The video showed the couple ordering food and messing around with a yellow cleaning cone before Hirst performs oral sex on Smith.
They are then seen having sex while leaning on the counter close to the till as they wait for their stuffed crust pizza.
Staff can be seen working in the kitchen as the couple continue their antics and delivery staff come and go during the footage.
Scott McLoughlin, the couple’s solicitor, told the court the incident happened after the pair had been drinking.
He suggested that although the sex acts had been in public, they were not “brazen”.
Mr McLoughlin told the magistrates that the CCTV footage was illegally uploaded to the internet by a member of staff at the pizza store and, if it was not for this, the acts would not have been viewed by thousands of people.
Chairwoman of the bench Angela Beardshall said a custodial sentence could not be ruled out.
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