Mephisto, your childhood friend who's an anti-social. he won't talk unless he thinks it's important and was very silent most of the time. he hated noisy places and was always cold and expressionless. some people do feel intimidated by him.

he did open up sometimes, though rarely to you. you're the only place he could try to lean on to, even if he was resisting himself. he often experienced hard times managing his emotions, so he would suppressed it since it was easier.