Who's the school shooter with the backpack supposed to be?

If anyone's into twee-pop Blew My Mind by Dresses is overwhelmingly adorable: https://www.youtube.com/wat…

Jimmy sobs uncontrollably, his face filling the entire frame. He is terrified. Jimmy is able to choke out the words, "for those of you who were too tied up to tune in last year, this is what you missed on Shamele—" before a bullet interrupts him by showering the camera with that thought, all the rest of his thoughts,…