Have you talked to your parents about the way he acts? How old is he? He sounds like he is a little kid and needs to be taught how to behave better, but from just that, I wouldn't peg him as a "demon." Trust me, I have have a brother that has done MUCH worse to me. I am not saying you should accept the way he acts, because you definitely SHOULDN'T ...... reply
I thought, in high school, I WAS that one loner kid. I had a handful of various friends from various clicks, but tended to spend most of my time alone because I had gotten tired of bullies and didn't trust people. Funny thing is, I thought I was massively unpopular. In class I would sit at my desk watching others and the teachers, making snide, sn...... 1 reply