Photobombers are annoying. They have no care for why you might be taking a picture; they just want to get themselves involved in it! This woman - presumably from Montenegro - was on holiday in Budapest, and wanted to get a commemorative picture taken in front of a major landmark. Having the Budapest tour bus in the background was a bonus. Having this guy mugging for the camera wasn't.
She probably wanted Fridman to remove the man from her picture, but like so many others she asked him to 'do something' with him instead. Fridman was at least a little sympathetic to her cause, though, because now he's made him blend in seamlessly with the background with a little help from a nearby fire hydrant. Remove the man from the picture? What man? We see no man here! Hopefully, she saw the funny side.