I've seen this a few times, where Voldemort constantly tries to convert the fem!Harry/twin sister because she's a girl and all and that's what you do with girls, don'tcha know. So this is my response to the cliché of converting the female Potter – I hope you enjoy ;)

"Join me and you will be great!" Voldemort insisted. He had just been reborn in the graveyard with the unwilling help of one Holly Potter and now he was trying to convert said girl to his cause. Currently, she was tied to a gravestone and was glaring daggers at him.

"Never!" Holly spat. Voldemort raised an eyebrow – or he would, if he did have an eyebrow. Or both eyebrows, for that matter. He shook his head, warding off his insecurities – they would not do at a time like this!

"Are you sure, Holly?" Voldemort whispered teasingly, shuddering at the lengths he had to go for his plan to work. "You could be great, you know...I could help you on the way to greatness."

Holly stared at Voldemort in shock, wondering how he had known what the Sorting Hat had said to her. Actually, he hadn't but it gave him a thrill of pleasure to know that he'd unsettled her and her mind told him as such.

"Why would you show loyalty to those at Hogwarts?" Voldemort continued, his voice playing games with Holly's mind and judgement. "They don't love you...they only love the Girl-Who-Lived. How many times have they turned on you? Even your redheaded friend turned his back on you, didn't he?"

A small part of Holly wondered just how Voldemort knew this but a bigger part of her was seeing the truth in his words. Nobody cared about Holly Potter – all they cared about was her fame!

"Join me and you will be the greatest witch ever to live," Voldemort asserted. He knew he'd won when Holly closed her eyes.

"Alright," she mumbled. "I'll join you." With a brilliant smile, Voldemort waved his wand and Holly's bonds dissolved. He then turned around to his Death Eaters.

"You all know what to do," he commanded. "And none of you are to touch the girl – she is now one of us."

The Death Eaters didn't look happy but they didn't dare defy their master, so they disappeared one by one. Voldemort caught sight of the Hufflepuff boy's dead body lying a short distance away and his red eyes brightened. He swooped over, grabbed the body and dumped it onto the gleaming cup Portkey, which disappeared with the body. That would terrify everybody and reinforce their minds against Holly. Should she ever succeed in leaving Voldemort, even if that chance was slim, she would find no welcome back at Hogwarts as the girl who had murdered her competition.

Returning to Holly, Voldemort offered his arm to her.

"Shall we, my Dark Lady?" he smirked, deriving satisfaction from her flinch. She took his arm and the two of them disappeared.

Phase one of Voldemort's plan was complete.

Back at Hogwarts, there was total pandemonium as the body of Cedric Diggory appeared with the Triwizard Cup and there was instant uproar. Everybody started screaming about how Holly had murdered Cedric just to win the Tournament and how they shouldn't have trusted her. A furious Ron was trying to convince Hermione that Holly was to blame.

"Who else could've killed him, Hermione?" Ron said. "If Holly was innocent then she would've returned!"

Hermione was going to point out that if Holly had murdered Cedric to win the Tournament then she would have left his body behind and returned herself to be crowned the winner but she refrained from pointing this out. She knew that most wizards didn't have an ounce of logic and, fairly certain she knew who had done this, resolved to talk to her parents at the earliest possible opportunity. Maybe they could get out before it was too late.

Albus Dumbledore was also certain that Lord Voldemort was behind this and he got a sinking feeling in his stomach. If Holly Potter had not returned then she was either dead or Dark and if she was dead, Voldemort would have sent her body back as well.

I sincerely hope that my worst fear will not come to pass, he thought.

It was the middle of summer and Lord Voldemort was very much enjoying the chaos he was causing. The Ministry of Magic refused to acknowledge that there was a possibility that he had returned and instead chose to pin all the blame on Holly, calling her a murderous psychopath who they should have picked up on earlier. The children of his loyal followers had reinforced this in interviews, calling her a psycho and someone who always picked on the innocent Slytherins.

He made sure to always deliver the Daily Prophet to Holly, who used to flinch whenever she saw the persecution of herself that everybody was advocating. But this had also worked to strengthen her resolve and now Voldemort could call her one of his best followers. She trained night and day, constantly seeking to better herself, and she had soon become the best duellist behind Voldemort himself. He would duel her every day just to test her skills and she was blossoming into quite the Dark witch. Her skills with the Unforgivable Curses were third only to his and Bellatrix Lestrange's.

He had then moved on to Muggle torturing. Every now and then, he would take a homeless Muggle or a runaway child that nobody would miss and Holly's job was to torture and kill them as Voldemort ordered. One day he had made her use Diffindo and make the homeless man bleed out; another day, she had been forced to torture a small child into insanity and then slit its throat.

At first, Holly had baulked at this. But then Voldemort had reminded her of how nobody truly loved her and even brought up the Dursleys. Whenever he mentioned her Muggle relatives, her face would darken and she would torture and kill the Muggle before her with such finesse that he was as close to feeling proud as he could get. The first few times, Holly had been horrified at what she had done but she had soon gotten over it and now thoroughly enjoyed it. Voldemort was actually a little concerned at how quickly she had taken to Muggle torturing and the Dark lifestyle in general.

At the end of the summer, Voldemort had suggested invading the Ministry and taking over and Holly was all too eager to agree. The fools at the Ministry had been denying his existence all summer and so it was really quite easy to invade, although it was mostly that easy because he had put Holly on the front lines and the sight of their precious Girl-Who-Lived fighting for Lord Voldemort. No matter how much they had smeared her, they didn't actually think that Holly would turn Dark and so it had come as a true shock. As a reward for her efforts, Voldemort had left her the Minister of Magic and she had truly had fun with him.

Bellatrix will have a wonderful new playmate, Voldemort mused.

After the Ministry, they had moved on to freeing the Death Eaters in Azkaban and soon, Voldemort had control of the entire wizarding world save for Hogwarts. However, with Holly's help, Voldemort had learned of a secret passageway right into Hogwarts through Honeydukes Sweet Shop and so it had been a simple matter to quietly kill the owners and occupy the shop.

"Who else knows of this passageway?" Voldemort questioned just before they embarked into the passageway.

"Weasley and Granger," Holly said with a soft smile, her green eyes glowing. "But they'd never think that we'd use it so we shouldn't run into any traps."

"Excellent," Voldemort said before turning to his Death Eaters. "When we get inside the castle, you may do as you please. Torture and kill as many Mudbloods and half-bloods as you wish but do not touch those we know to be on our side and any pure-bloods, even the blood traitors."

The Death Eaters looked a little annoyed at that but they were being promised a nearly unlimited playing ground! What could be better?

Holly had been right; Ron and Hermione hadn't thought to tell anyone of the passage under the old witch (although Hermione had managed to flee the country with her parents and therefore couldn't be held accountable for this). The first students to come across the invading Death Eaters were quickly silenced so as not to raise the alarm but once everyone was out of the passageway, torture and slow deaths spread all over the castle. Voldemort and Holly went straight for the Headmaster's office, which was relatively easy to get into. Dumbledore was on guard and though he could stand his ground quite easily against Voldemort, he had not seen Holly and so was taken completely by surprise when she Disarmed him from behind.

"Any last words, old man?" Voldemort said triumphantly. Dumbledore looked straight at Holly.

"Why, Holly?" he said sadly. "Why would you do this?"

"Because you don't deserve me," Holly said angrily, her eyes flashing. "You could have stopped the hate I experienced in my first year but you didn't – you were perfectly content to sit around and let the students persecute me. In my second year, you could have stood up and told everybody that I wasn't the Heir, or at least told them that I was innocent until proven guilty. And last year, you could have provided proof that I was innocent of putting my name in the Goblet – but you didn't. You've let me down too many times."

"If I had told the students about what you had lost the points for, Hagrid would have been in trouble," Dumbledore said. "I didn't think you wanted that. And I did not know for sure that you were innocent in your second year because you didn't tell me when I offered you the chance. And there was absolutely no proof that you were innocent last year –"

Holly's eyes flashed again and with a swipe of her wand, scarlet blood started spurting out of a gash in Dumbledore's robe. Gasping for breath, he looked up at Holly but the last thing he saw was the hate in her emerald eyes before his vision went black.

"I would have preferred to have tortured him slowly to death," Voldemort commented idly.

"He irritated me," Holly snorted.

"Indeed. And now, I believe, we come to a problem."

Holly was about to ask what the problem was when she felt her wand leave her hand. Voldemort caught it, smirking lazily.

"You fell right into my trap, dear Holly," he said. "I knew that I could use you and your pretty face to demoralise the wizarding world and make it easier for me to take over. But you should know that I don't share power with anybody."

"You betrayed me!" Holly hissed. She scrambled for Dumbledore's wand but with a flick of his wand, Voldemort had snapped the wand cleanly in half. Another flick later, Holly was kneeling on the ground.

"I must say, you have exceeded my every expectation," Voldemort said. "But I knew that there would come a time when you would feel that you were stronger and try and wrest power from me – and I couldn't have that. While in the Ministry one day, I took a stroll down to the Department of Mysteries and found a prophecy that had both of our names on it. Do you want to know what that prophecy said?"

Holly fixed Voldemort with her most evil glare.

"Of course you do. 'The one with the power to vanquish the Dark Lord approaches...born to those who have thrice defied him, born as the seventh month dies...and the Dark Lord will mark them as his equal but they will have power the Dark Lord knows not...and either must die at the hand of the other for neither can live while the other survives...'"

Holly's eyes widened.

"I only knew the first part and that was the reason I attacked you when you were a baby," Voldemort continued. "If I had known the rest, I would have left you alone and never tried to kill you. But how interesting it is...it does not say that you will kill me but that either of us could kill each other. And, as I'm sure you understand, I must kill you. It's nothing personal."

Holly was mentally berating herself for being so stupid and the images going through her mind were quite amusing to Voldemort.

"Goodbye, Holly Potter." With a flash of green light, Holly Potter collapsed, her green eyes open and unseeing. Voldemort continued to watch her until he was certain that she was dead and then he was about to turn away when he noticed her foot twitch. One little movement had given her away and Voldemort sent another Killing Curse at the girl, killing her for good. With a flick of his wand, her head, legs and arms severed themselves from her torso, to ensure that the girl could not return to her body again – or, if she did, that she could regret it.

'Of course I was going to kill her,' Voldemort smirked. 'Yes, she was useful but all of them turn at the slightest provocation. How else would I keep my Death Eaters in line? By treating them as equals? If you treat somebody as an equal then it gives them the right to betray you – a right that I seized before that foolish girl.'

Lord Voldemort had won. And all because one girl had given in to temptation and joined the Dark Side.

I really like the name Holly and I'm probably going to use it in a fic I'm planning but the character I was imagining while writing this? I despise her with the burning passion of a thousand suns.