Karma will eventually bite him in the ass.
People like him often end up eventually picking on the wrong person .When they do and end up in the hospital(or morgue) as a result, they'll have nobody but themselves to blame. Something similar happened to a YouTube prankster who went around threatening and harassing people for views. He unsurprisingly ended up getting shot by one of his victims, while pretending to rob people as a "prank".
It just blows my mind that certain people act as if not having friends is a cardinal sin. It never occurs to them that people can be shunned through no fault of their own such as being the wrong race in certain neighborhoods, being perceived as gay,having certain facial features, being poor, being disabled or some other reason.
Not to mention teachers can sometimes be the biggest bullies, especially if you differ from the norm.