Charlotte Crosby and Stephen Bear were all over each other in London last week.
The pair attended MTV's Brand New gig at the Electric Ballroom in Camden Town, London and kissed and cuddled each other in front of onlookers.
A source told The Sun: "Charlotte was all over Bear and he was absolutely loving it.
"They were inseparable. They spent a long time kissing in the middle of the crowd and had their arms wrapped around each other.
"At one point Stephen cheekily grabbed her bum, too. The concert was open to the public but they didn't care who was watching."
The pair have been linked since December but Charlotte recently insisted they are simply friends and co-stars on MTV show 'Just Tattoo of Us'.
She said: "We're just very good friends. Just good friends. We spent a lot of time together, but that was just filming 16 hours a day for 'Just Tattoo of Us'.
"When we were filming, we were constantly play-fighting with each other, or doing something to wind each other up."
The romance comes as a surprise as it was believed that initially the pair did not get on while filming the show.
An insider previously said: "Charlotte and Bear have not been seeing eye to eye on their new show. Charlotte finds Bear annoying and unprofessional. She doesn't think he has earned his fame.
"A lot of people think she is finding it difficult to share the limelight with him after hosting a TV series on her own in the past."
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