A more substantial question: How is that mean guy (who tortures greyjoy) is related to Jon Snow?
He's not. The last name Snow is used for bastards from the North:
Bastardy - Game of Thrones Wiki
Jon Snow: "What's my name?"
Samwell Tarly: "Jon Snow."
Jon Snow: "And why is my surname 'Snow'?"
Samwell Tarly: "...Because you're a bastard from the North."