14His Parents Hated Him
Aside from how most of the Wizarding World views him, Sirius Black is a lovable character. He was brave and loyal, if not rough-around-the-edges (though one could blame wrongful imprisonment in a maximum security penitentiary for that). Still, his positive attributes didn't help him when it came to his family. A
stuffy, stuck-up bunch, the rest of the Blacks hated him. He was the black sheep (no pun intended) in his family, and they had no trouble reminding him that he stuck out like a sore thumb.
Still, the only reason this was the case was on account of where his loyalty stood. While the rest of his family was busy saluting all of the pure-blood wizards of the world, Sirius was rooting for the underdogs (his animagus was a dog itself, but again, no pun intended). Still, no matter how difficult his family might have made his life, Sirius was serious about standing on the right side of history — and at this point, pun may as well be intended.