J Lesser is the stage name for Jason Doerck (born December 19, 1970). Doerck recorded as Lesser for much of his career; https://www.last.fm/music/Lesser but appears to be using J Lesser for releases in 2024.
These are photos from concerts where J Lesser played, so they may be of other bands that played the concert as well.
Negativland / J Lesser May 28, 2024 Philadelphia, Pennsylvania, United States Uploaded by Davidan