"Never used an Unforgivable Curse before, have you, boy?" Bellatrix yelled. She had abandoned her baby voice now. "You need to mean them, Potter! You need to really want to cause pain — to enjoy it —"*

"Indeed," said a familiar high, cold voice behind him, and Harry frantically dove for cover, unconsciously putting himself at the perfect angle to curse Bellatrix, who dropped to the floor in devotion, forgetting Harry. Harry raised his wand, but the pain in his forehead temporarily blocked all thought. He couldn't decide what to cast. After a moment, his head cleared, and he stared at Voldemort in horror. He suddenly realized that he was alone in an empty room, with no escape and assistance far away, with the most powerful dark wizard AND the most powerful dark witch of their century.

"Potter, if you want to use that curse, focus on her actually being in pain, not on your anger. The Dark Arts, like most higher magics, rely on focusing your worthless mind," continued Voldemort.

"My Lord!" exclaimed Bellatrix. "Master, I am sorry—"

"Bella." hissed Voldemort dangerously. "I told you to get me the prophecy. Consider it your punishment." He switched to glaring at Harry again.

Harry gaped at the man. Why wasn't he trying to kill him? More to the point, why had he encouraged Harry to curse his favorite Death Eater? Harry's brain-to-mouth filter shut down as his sense of reality tried to reboot. "Why would you help me curse your best follower? Isn't that counterproductive?" Then he slapped his hand over his mouth. Nothing good ever comes of talking to Voldemort.

The Dark Lord, slightly amused at his antics, replied, "Why not? Even if you do succeed, she is strong enough to deal with a little pain. Did you know one of the less-advertised effects of the Cruciatus Curse is improved reflexes? Repeated applications stimulate the nerves."

Harry stared at the Dark Lord in shock, his sense of reality flying ever further away. "Is that why you curse them? I thought you just liked seeing people in pain."

Voldemort laughs. "Well, I won't deny that it is a happy side-effect. I also find pain and fear are wonderful motivators. However, I cannot deny that I do enjoy witnessing the pain of others." He grinned at the disgust on Harry's face. "Haven't you ever cursed someone who annoyed you? I find it quite therapeutic."

Harry glared at the dark lord in disgust, keeping his want on Bellatrix. The level of sadism he displayed was sickening. The man's appearance was also quite grotesque. However, he was undeniably terrifying. I can't fight them both alone. Harry was in a standoff. Maybe if he bought some time the Order would catch up to him. Well, Voldemort did seem strangely chatty.

"I tend to be the one people are cursing, actually. Unlike you, I have a conscience."

"Quite inconvenient, that," Voldemort responded with dry amusement.

Harry's brow wrinkled as another thought occurred to him. "Why do your followers cast that curse on anything that moves if doing so makes their victims stronger?" That really didn't make any sense.

"Stupidity, mostly. However, it does have its time and place. Most people can't withstand the pain, so it is wonderful for breaking down any resistance to legilimency. Plus, most torture victims aren't intended to survive. Side-effects are irrelevant."

"The torture curse also has its uses on larger battlefields. There are two curses that can break through any shield and which can be cast with minimal training. The Cruciatus Curse and the Killing Curse. When my Death Eaters attack en mass, a certain percentage always manage to hit each other. When there is a chance of friendly fire, I would much prefer they use the torture curse than the killing curse. Letting them kill each other rather defeats the purpose, and most enemies who are hit are too shocked to dodge the next spell, which is usually fatal. Given that, I don't think I need to explain how advantageous it is to have curses no one can shield against. Even an incompetent can become a force on the battlefield if they are able and willing to cast those two curses."

Harry gaped speechlessly at his enemy. Somehow, his thought process had been that mean, evil people cast cruel curses for no reason other than that they could. He believed that Death Eaters were sadistic with no logic to any of their actions. It seemed that was not the whole story.

"What? Did you really think I would train my forces to fight that way without a reason? I didn't become the most powerful dark lord of our century by sheer stupidity, Potter. If sadism and narcissism were enough to do what I have done, the Malfoys or Blacks would rule the wizarding world." Voldemort declared angrily. He was actually offended, if Harry was reading his face right. It was kind of hard to tell without a nose. "Or maybe the Potters. From what I hear, your father and his gang were real pieces of work."

"Hey!" Harry yelped in indignation. "Don't you dare insult my parents!" He nearly took his wand off Bellatrix to curse her master, but recalled that he was alone with two of the most powerful and feared wizards of the century. He didn't stand a chance in a straight-up fight. He needed to delay them more, somehow. After a moment's frantic pondering, he blurted out, "What about the Longbottoms? Why are they in the hospital if the torture curse is so good for them?"

Voldemort snorted. "They were weaklings. Their minds snapped, not their bodies. As for any physical injuries, do you really believe the only curse used to torture enemies is the Cruciatus? And have you ever heard the words "too much of a good thing"?"

Harry stared at him. He should be mad, but the conversation was just too surreal. Eventually he couldn't help himself. "Why are you telling me all of this?"

Voldemort sneered back at him. "You asked."

They stared at each other for a minute. "So, are you going to curse her or stand there all day, Potter? Or do you want a demonstration?"

Harry looked around wildly. "Um…"

Thankfully for Harry's sanity, this is when Dumbledore arrived.