None that we know of. Tom Riddle got sorted into Slytherin despite being half-blood, so the Sorting Hat apparently doesn't take the house's prejudices into account. In short, there could be, but we don't know of any.
Yes. It is unusual, but as long as they will have a devious, or potentially evil future, or already be evil, like all the other Slytherins, they can be.
Nyphodora Tonks was in Hufflepuff at Hogwarts School of Witchcraft and Wizardry
Lucius Malfoy's son is Draco, and he is a Slytherin. Draco's son is Scropius, and his house is not stated in any of the books.
he is a direct descendent of salazar slytherin, so the sorting hat probably sensed that. Plus slytherin isn't only for pure-bloods, as Snape was in that house, and he was the Half-blood Prince. Also, even Harry is a half-blood, and he was told by the sorting hat that he would do well in slytherin.
No. Cho was a Ravenclaw.
If you are talking about a romantic relationship then no.
It is unknown which house Aurora Sinistra was sorted into. Since nothing is known about her personality either so it is impossible to guess which house she was sorted into. As for why people list her as Slytherin, it could be that one person decided to list her as Slytherin and others copied or it may simply be that people want to fill up the Slytherin rostra.
He was also afraid he would not be picked at all.Not slytherin.....Not slytherin
The Sorting Hat initially wanted to put Harry in Slytherin; but seeing as Harry already had a bad impression of Slytherin he asked not to be put there, and the Sorting Hat put him in Gryffindor, if Harry hadn't said, "Not Slytherin, not Slytherin" than he most likely would have been in Slytherin. but he was placed in Gryffindor.
In Harry Potter and the Philosopher's Stone, Harry was sorted into Gryffindor house in chapter seven, "The Sorting Hat".
Slytherin House. Says so in the first book when he's the last one sorted
Cunning is a trait of people sorted into Slytherin - it is not the name of a character.
Nyphodora Tonks was in Hufflepuff at Hogwarts School of Witchcraft and Wizardry
Hufflepuff, easily, yet I'd probably get sorted into Ravenclaw or Slytherin.... What relevance does this have to anything by the way?
The fanfiction you are referring to is likely "Slytherinβs Potter" by Stargon1. In this story, Harry gets sent back in time to the Marauders' era, is sorted into Slytherin, befriends Snape, and eventually disappears after Snape tortures him.
The man's face in which the basilisk slithers out of in Harry Potter and the Chamber of Secrets is Salazar Slytherin. He was one of the founders of Hogwarts known for his distaste of muggleborn wizards. He built it so his heir could cause terror for the muggleborns of the school with the basilisk.
Lucius Malfoy's son is Draco, and he is a Slytherin. Draco's son is Scropius, and his house is not stated in any of the books.
No, you are picked based on your answers. For example: Q. Black or white? White= Gryffindor/Ravenclaw Black= Hufflepuff/ Slytherin