I'm with violet sky on this one, I've worked with young people for years as a social worker and foster carer & I found that shouting at them or hitting them whoever did it, doesn't work. I'd speak with his parents about how to manage it, its highly likely that they can't stop him either, but I'd mostly ignore him & just say you don't like how he's treating people and spend your time with people who are pleasant to be with. I love Barmy old Bat's way of saying 'you don't seem to like me, so you won't want a pressie for me.' and let him dwell on that. If it would work, I'd say fine, shout at him, but in my experience it just increases everyone's anger without achieving whereas ignoring and withdrawing privileges makes them think about what they're doing. If you could fast forward 5 yrs or so, you'd probably find a delightful young man ashamed of his actions but this is a stage a lot of young people, me included, have to go through.