Girl fights always seemed the worst, but that's not a fight, that's just an attack. The poor girl clearly wanted no part of it and the **** just attacked her repeatedly, the stamp when she was down was particularly vicious and should, in a sane world, result in a heavy punishment.
It happened when I was a kid as well, but the amount of people who goad them on now or pile on seems to take it to another level. Trash like this need putting on a register and keeping an eye on, as they are going to end up seriously hurting someone. Fucking scum