Your comments

I think this rule shouldn't be too trict. Especially for names like "Malfoy".
Because there is the option to play a pureblood-character. And as we learned from the books- all pureblood-familys are related. So if you play a Malfoy- of course you are related to the Malfoys from the books. But as long as Draco is not your Cousin or your Grandfather, I think, there shouldn't be any problem...