The 'Domino' singer addressed reports that emerged after she was snapped arm in arm with Kenny Hamilton, who described her on Twitter as his "fav British lady", on a night out in London on Wednesday (September 12).
"Oh boy...Some people just make up anything," she tweeted. "I get jokes reading about my "life" when its complete lies. Some people really need to get a job :\."
Hamilton has been trailing Bieber in London while the 'Boyfriend' singer promotes his tell-all book Just Getting Started in the UK this week.
Just Getting Started, which was released yesterday (September 13), includes references to his paternity scandal and issues with the paparazzi.
Jessie J recently announced on Twitter that she is to shave her head live for Comic Relief next year.