Board Thread:General Discussion/@comment-24810590-20140626062545/@comment-679780-20140807202314

Sonic and Mario may appear buddy-buddy for the fans, but behind scenes where Mario talks openly when not in games, believes himself better than Sonic and doesn't forget to remind Sonic often when he is around.

Also Mario is a sociopath but that isn't really a secret as it's evident in almost all of his games. (Imagine what Mario would say while gleefully crushing goomas with the heels of his italian leathers.)