A Bollo is someone who visits hardcore(genre) concerts and acts like a fucking jerk. He is all about to hurt people with his violent dancing and brutal moshing.
Bands like Hatebreed, Born from Pain etc. are his targets.
AND NO! A Bollo is not a mixture of Hopper and Emo like: skinny jeans, fat jackets, hip hop caps, long black hair.
People saying this talking shit and just have no idea.
(exactly the sort of people who dont know what a real emo is anyway...)
But some hardcore Labels signed HipHop Groups with hardcore influences.
That could be the reason some people dont get the term Bollo right.