Author's Notes: Written for Lost In The Lies' "My Scenario, Your Story" Challenge on the HPFC forum, in which the entrant chooses characters, Lost In The Lies writes a brief scene with them, and we have to build a story around that scene.

Bellatrix/Sirius. Blackcest, dub-con. Not explicit, but rated M because I'm a touch paranoid. Takes place before Sirius runs away.

)O(

"No, Sirius, like this."

Sirius Black looked up at his eldest cousin, Bellatrix, and watched as she rearranged his hand on his broomstick. She smiled at him as she let go, brushing her hair out of her face. "There you go."

"Maybe we should wait for Uncle Orion…" Nine-year-old Narcissa trailed off as she looked up from the game she was using to amuse three-year-old Regulus.

"Nonsense, Cissy. Sirius's a Black – he'll be a natural flyer," Andromeda said, rolling her eyes at her two-year-younger sister.

"Just what Andi said," Bellatrix said with a nod. "Anyways, he's six, it's time he learns how to fly. And we're his cousins; we've got to teach him."

"Yes, just what Bella said. We Blacks have to stick together," Andromeda said, Narcissa nodded along.

"Right!" Sirius chimed in, Regulus nodding and giggling as he clapped his hands.

Sirius sighed, and sat down in the stands. Bellatrix had taught him well, been convinced – as had been the rest of the family – that he would be playing for the Slytherin Quidditch team. When he had been sorted into Gryffindor, Bellatrix had cornered him, seventh year to his first, and told him that if he even thought about using what she had taught him to play for Gryffindor, she would kill him. James, who had seen Sirius flying, had asked him why he didn't join the team, but Sirius had maintained that he didn't want to.

So he, Remus and Peter sat together during Quidditch games, watching James fly, and Sirius wished he could be out on a broom as well…

"Shove over, I need to see my cousin."

Sirius jerked out of his reverie, and was surprised to see Bellatrix standing over him, both Remus and Peter shrinking away from her with looks of mild terror on their faces.

"What are you doing here, Bellatrix?" he asked, standing up. His cousin was twenty-three now, and she avoided Hogwarts, and especially Sirius.

"Family business," she said shortly, grabbing his arm, and dragging him away from his seat.

"But the game–"

"You can miss the game."

Sirius cast a helpless look at his friends, and followed Bellatrix along the row and down onto the grounds.

The afternoon was cold, clear and frosty, and Sirius shivered as his cousin dragged him in the direction of the Forbidden Forest.

"Where are we going?" he asked, teeth chattering.

"Just inside the trees," Bellatrix said, not looking back at him. "Little privacy."

"What do we need privacy for?"

She didn't answer, but walked into the forest, far enough to be shielded from the stands. Then she turned around, and looked at Sirius.

"Well?" he said. "Why are you here? You haven't set foot in Hogwarts grounds since you finished school."

"I had to come talk to you," she told him. "Cissy was going to, but she went and got engaged to Lucius Malfoy, and the blood traitor ran off with that Mudblood, so that left me."

"Left you to do what?"

"To teach you."

"What?"

Bellatrix blew out a long, slow breath, eyebrows drawing together as she appeared to consider what to say.

"Remember when you were six, and I taught you to fly?" she said at last.

"Of course. I was just thinking about that, actually."

"Well, you didn't think that was the only thing the family wanted you taught, did you?"

"I… don't know… I don't understand…"

"When you were six," Bellatrix said, taking a step towards him, "I taught you how to handle a broomstick."

"Yes, I know that…"

"And now that you're sixteen, there's something else you need to learn how to handle."

Sirius gulped and stepped backwards. Bellatrix's eyes looked a little too bright, under her hood, and she was smiling almost demonically.

"Don't be scared," she breathed, advancing. "I'm just going to be your teacher."

"I don't understand…" Sirius backed up, away from her.

"You will," said Bellatrix. She lowered the hood of her cloak, and the icy wind caught in her black curls, lifting them into a dark halo around her head.

Sirius swallowed hard, still backing up, faster now, trying to get away from his cousin. She looked positively possessed, and he knew that if it came to a fight, she would win.

Get away from her, just get away fast…

His foot caught on a root, and he stumbled backwards, trying to catch himself, but only succeeded in scraping both his hands when he landed hard on his back.

Bellatrix stepped up to his side, and knelt, smiling a little.

"Let me see your hands," she said, and Sirius held out his arms, cheeks burning. Bellatrix examined his palms, tilting her head to look at the scrapes.

"No permanent damage," she said, and raised his hand to her lips, kissing it lightly.

"What do you think you're doing?" Sirius asked, pulling away from her.

"I told you, I'm going to be your teacher."

Everything clicked.

Sirius sat up and tried to push himself away, eyes wide with horror. Bellatrix rolled her eyes and caught onto the front of his robes.

"Now look, Sirius," she said, and her voice went from sensual purr to sharp and harsh. "I don't want to turn this into a big production, but if I have to tie you up, I will."

"What?"

"It will be so much easier on both of us if you just stop fighting."

Sirius swallowed hard. "Bella, I don't think–"

"Don't worry, love. You're a Black. You'll be a natural."

She gently pushed him backwards, so he was flat on his back on the forest floor, and climbed atop him.

"Why are you doing this?" he whispered, shrinking away from her as best he could.

"I told you, Narcissa can't because she's engaged." Bellatrix began expertly popping open the buttons of Sirius's shirt. "Don't act so horrified, darling, it's Black family tradition to be sure that the heirs are deflowered by their cousins. It's the best way to keep blood pure. After all, we wouldn't want your first time to be with some filthy little Mudblood, would we?"

Sirius made a soft noise of protest. "It's wrong…"

"Nonsense," Bellatrix breathed. "We Blacks have to stick together, you know."

)O(

Fin