Disclaimer: I do not own Harry Potter.
(A.N: Just a note here, I don't think Tonks would have been a Slytherin; it just doesn't fit with her character. However the idea wouldn't go away, so that's why I made her a Slytherin for this fic; it wouldn't have worked with any other House. Hope that explains things.)
By Silver Sailor Ganymede
Nymphadora Tonks was in a state of shock. To say anything less would have been a lie. It hadn't come as a complete surprise where she had been sorted, especially considering what her mother had told about her side of the family, but she still couldn't quite believe it. Both her parents had been Ravenclaws, yet here she was sitting in a pit full of venomous snakes. She had become a Slytherin.
Nymphadora clearly remembered what her mother had told her to do if she did become a Slytherin – don't tell them your real name if they ask for it.
"Use my maiden name rather than your father's," Andromeda had said. "If they think you're a Black then you'll be fine. If they think you're a pureblood then you'll be fine. But if they figure out that you're father was a muggleborn then that will make you a mudblood in their eyes. Better to lie and save yourself a lot of trouble." That was the only time Nymphadora could recall her mother acting like a Slytherin, like a pureblood, like the Black she was born as. Nymphadora didn't like that side of her mother, not at all.
Suddenly two girls came in to the room, both with smug looks on their faces and both with the characteristic silver eyes that marked them as purebloods who were related somehow to either the Blacks, the Malfoys or the Rosiers. The three most notorious pureblood lines, the three Houses that held more dark wizards than any other, were linked not only by their blood but by that common trait: cold, emotionless, silver eyes. Snake's eyes: eyes that Nymphadora had inherited from her mother.
"I'm Genevie de la Nuit, and this is my friend, Venus Cytherean," the black-haired girl spoke, gesturing to herself and the petite blonde next to her. "It seems there are only three girls in Slytherin this year. Would you mind telling us your name? I really can't remember it, I'm afraid."
The question was innocent enough but Nymphadora froze, wondering what she should do. She could always do what her mother had suggested and tell them her surname was 'Black', make them believe that she was part of her mother's family, a family she had never known or regarded as her own. On the other hand she could tell them the truth, let them know that she was what they'd call 'a filthy mudblood.' But what would be better, to suffer because of the truth or to end up living a lie for the next few years? She honestly didn't know.
"Are you listening to me?" the girl, Genevive, snapped finally, evidently growing impatient. "I asked your name and you still haven't replied. It's not really that hard a question to answer, is it?"
Hah, what did she know? It was a far harder thing to reply to than anyone would have guessed, but she had finally made up her mind.
"My name's Nymphadora," she said and the Genevive raised an eyebrow.
"Unusual name – I suppose you must be a pureblood, but what's your last name?"
"It's Tonks," she replied.
"Oh wonderful," Venus drawled, "Our roommate's a mudblood."
Mudblood, mudblood, mudblood… she had sealed her own fate, but to be honest Nymphadora Tonks had never felt happier about anything in her entire life.