Author's Notes: Written for meira16's "The Nature of Magic" challenge on xoxLewrahxox's Bellatrix Lestrange: The Dark Lord's Most Faithful forum.

The challenge is to write a fic that discusses at some point something relating to the nature of magic - what it is, how it evolved, how it actually works, what Dark magic is - anything like that.

Exactly 555 words.

Warnings: Sexual content and sadism

)O(

The Muggle was bound and gagged, on his knees. Bellatrix's eyes were wide and excited as she looked from him to the Dark Lord.

"What am I to do with him, my Lord?" she asked eagerly. She had only been marked a few days ago, and the thought that she was being given a Muggle pleased her.

"Torture him, Bellatrix," the Dark Lord said simply.

Bellatrix looked at the Muggle, then raised her wand to point it at him. "Should I use the Cruciatus curse, my Lord?"

"That is right." The Dark Lord's tone was mildly impatient.

She ran her tongue around her lips, hesitating for a second, then said, "Crucio."

The Muggle didn't even move, only looked more terrified than ever. Bellatrix scowled impatiently, waving her wand. "Crucio! Crucio!"

Voldemort sighed and shook his head. "You are not doing it right, Bellatrix."

"Clearly," she muttered, impatient with herself. "What am I doing wrong?"

"You are not enjoying it," he told her. "You must enjoy the man's pain to be able to cause it. You must gain pleasure from it."

She looked at him, confused, and he looked back. Bellatrix was unwilling to argue his point, but she didn't understand it.

At last, after several long moments, the Dark Lord sighed impatiently.

"Do you know why Dark magic is different from other magic?" he asked, then continued without waiting for her to give him an answer. "Dark Magic stems from passion, from pleasure… from lust…"

"L- lust, my Lord?"

"Yes, Bellatrix…" His crimson eyes fixed upon hers. "Lust… Lust is such a strong feeling, that magic could not help but be born of it…"

She swallowed.

The Dark Lord seemed to ponder for a second, then he took Bellatrix firmly by the waist and pulled her down, setting her on his lap. One arm wrapped around her waist to stop her from moving.

"Curse the Muggle, Bellatrix," he purred in her ear. Bellatrix's heart was beating fast with nerves at being in such close proximity to such a powerful man.

"M- my Lord?"

"Do it!"

She raised her wand and aimed it at the Muggle again.

"Crucio…"

No effect, but Bellatrix was distracted by the Dark Lord's hand, travelling up the inside of her thigh.

"Try again…"

"C- Crucio." Once more, the spell had no effect. His fingers were between her legs now, stroking the most sensitive parts of her, and she turned to him, eyes wide and desperate. "My Lord, I- I cannot concentrate when you are doing this to me…"

"Don't you remember what I said, Bellatrix?" he purred. "Dark magic comes from lust…"

One finger slipped under her clothing, inside of her, and Bellatrix gasped. She did indeed feel passion rising inside her, her breath coming fast and heavy.

"Crucio."

The word turned into a moan, as the Dark Lord pressed a second finger into her, and her back arched. The Muggle let out a cry through his gag, surprising her.

"Good," the Dark Lord breathed. "Do you feel lust, Bellatrix?"

She nodded, cheeks blazing. His fingers were pushing in and out of her quickly now, and stars were popping in front of her eyes.

"Once more," he whispered, and Bellatrix could scarcely form the incantation.

"Crucio!"

She heard the Muggle scream seconds before she lost control in the Dark Lord's arms.

)O(

Fin