Besides being the role of female actress Juliette Lewis in the Oliver Stone film "Natural Born Killers" there is more than one artist with this name (see links in the Wiki sources):
These are photos from concerts where Mallory Knox played, so they may be of other bands that played the concert as well.
Butserfest Sep 10, 2016 Petersfield Uploaded by Jwicks
Slam Dunk 2016 May 29, 2016 Birmingham, England, United Kingdom Uploaded by Jess Fitzgerald
Vans Warped Tour ‘15 Aug 2, 2015 Denver, Colorado, United States Uploaded by Sienna Araya King
Vans Warped Tour 2015 Jul 30, 2015 Bonner Springs, Kansas, United States Uploaded by Kansas City Concert Fiendz