Mathew Black was the son of one of the most powerful and wealthy families—naturally, a long line of Slytherins. So it was no surprise when he was sorted into Slytherin as well. The only real surprise came when he befriended students from Gryffindor, particularly Ron Weasley. This didn’t sit well with the other Slytherins, but they never openly commented on his friendship with a Gryffindor—especially a Weasley.