it's apparently simply not possible for a Slytherin to have a non-sinister history
That's very true, if mainly in the lack of many Slytherin characters' history. When we do get a slight fill-in on a Slytherin's history, it does have sinister implications like you've said. But with other Slytherins like Pansy Parkinson or Millicent Bulstrode, we don't really know. All we know is that Pansy wears a gold watch and is a "mean popular girl." Yep.
And I do agree with you on the mixed thing. I always imagined Blaise's father being Italian or of Italian descent -- hence the Italian last name. Or Zabini could be Blaise's mother's last name and she herself is racially mixed. So many possibilities here.
Re: For once, using my default icon on purpose.
That's very true, if mainly in the lack of many Slytherin characters' history. When we do get a slight fill-in on a Slytherin's history, it does have sinister implications like you've said. But with other Slytherins like Pansy Parkinson or Millicent Bulstrode, we don't really know. All we know is that Pansy wears a gold watch and is a "mean popular girl." Yep.
And I do agree with you on the mixed thing. I always imagined Blaise's father being Italian or of Italian descent -- hence the Italian last name. Or Zabini could be Blaise's mother's last name and she herself is racially mixed. So many possibilities here.