Summary: Snape is no longer the only spy for the light side. Callidora Black is a Hogwarts student with her own connections to the dark lord through the death eaters that raised her, but she wants to fight for a more noble cause. Following the footsteps of her brother she joins the Order of the Phoenix, and works alongside Snape as his only ally and friend on both sides of the war. The two spies soon realize that the only people they can rely on are each other. [Snape x OC]

Summary: Story starts at the end of The Goblet of Fire. Callidora is the estranged sister of Sirius Black, born after he was disowned. The story begins at the end of her seventh year. AU

Disclaimer: All Characters and events belong to J.K Rowling except for the character Callidora Black.

…

Chapter One

She sat in the Headmaster's office, left alone with the stunning Phoenix that seemed to be staring daggers right at her. It was not easy getting this meeting. She had to turn to the head of bloody Gryffindor house to beg for this to be set up. It was humiliating. Her mother had probably turned over in her grave. She could practically hear her shrill voice now. "You are a member of the honorable House of Black, and Black's do not beg nor grovel for anything," she used to say. The thought almost made her laugh. If her mother would have been mad about her asking favors from a Gryffindor she would have disowned Callidora for what she was about to do. If the Headmaster doesn't send her straight to Azkaban that is.

Trying not to think about that, Callidora pulled herself back into the moment she was in now, deciding she would worry about that when the time came. She crossed her legs and tried very hard to be irritated that she was missing Ancient Runes and that Dumbledore was late, hoping that this would mask the stomach turning nervousness she was feeling right now. It didn't, and she nearly jumped out of her skin when she heard the door to the office open. She watched the Headmasters, her heart beating a little faster and her back getting a little straighter with every step he took as he crossed the room and sat down at his desk facing her.

"Miss Black!" he exclaimed. "It is always a pleasure to have a chat with one of my students. Would you care for a lemon drop?"

Callidora was surprised at his kindness until she realized that, unlike her, he had no idea why she was here. "No thank you sir," she replied turning down his candy, "and I'm afraid this is more than just a chat."

The Headmaster's expression sobered a bit as he said, "When Minerva told me you came to her practically begging for a meeting with me so close to the end of the year, when we are both so busy, I assumed it would be concerning a very pressing matter. What, though, I have not been able to figure out on my own."

His eyes met hers as he said this, and she felt her hands begin to shake. "I am very sorry to take up your time sir, and I know you are very busy with the school year ending, not to mention Cedric's Death, and I can assure you I would not be here unless it was very important. Which it is!" she rambled on apologies, partly stalling before she had to get to the point and partly trying to play the innocent school girl part until that image was shattered for her for good. "I need help, professor, and at this point I think you are the only one I can turn to."

A glimmer shone in Dumbledore's eyes as she said these last words. "And I intend to give you all the help you could need." He assured her with a knowing smile on his face. "You just have to tell me what it is you need assistance with." How he could be so cheery, Callidora didn't understand, they both knew the dark lord was back, and the tone of his voice implied that he knew why she was here too. This being said, she had never quite been able to figure the headmaster out, and she knew that he, unlike most people, would notice if she tried to enter his mind through legilimancy.

"I'm not sure if you are aware headmaster, but my parents were both dead by the time I was eight." She didn't know how to begin asking for what she needed, but she figured a little sympathy to start out with wouldn't hurt.

"Yes," interrupted the Headmaster "and if I recall correctly you were taken in by your Aunt Druella."

"That's correct, but I was really raised by my cousins." The headmasters glowered at this statement. He, of course, knew they had a part in her life, but she suspected he didn't know how big a part. "The dark arts have always appealed to them, just as they appealed to my brothers," she admitted slowly, "Just as they appeal to me."

She let this sentence hang in the air as she carefully watched the Headmasters expression. He was silent, waiting for her to continue. She pulled air into her lungs in preparation for words she knew were going to be hard to say.

"It is not something I am proud of, that's why I'm here, but I was not forced into anything I did. It is important that you know that. I asked for it all, and now the dark arts are a part of me I cannot get rid of," sadness dripped from her voice as she spoke these incriminating words. "Despite that, though, I have realized that a life tainted with death and evil is not the life I want to live. That is why I need you to help me."

The headmaster spoke now, his voice was controlled but eyes shone with a bitter mix of emotion. "As much as it saddens me to hear you speak these word, my child, I am glad you did." Callidora's heavy heart lightened a bit at these words, though she told herself not to hope for much. "I assume you want me to hide you from your family and other Death Eaters," he didn't pretend to be unaware of her cousin's affiliations, "before they ask you to join them that is." Dumbledore finished.

Callidora's heart nearly broke at his words. He really didn't know as much as his eyes made it seem, and now she was being forced to speak out loud the words that could ruin what little faith he had in her. She looked down at her hands folded in her lap as she spoke. "It is too late for that, sir," she spoke coldly before turning her emotionless face up to meet his eyes.

The Headmaster leaped up from behind his desk and was kneeling before her in a second. His frail looking hand gripped her left wrist with surprising strength. His other hand shook with rage as he violently pulled the arm of her sweater up to her left elbow.

The black skull and snake that stared up at them from her arm stood out starkly against her pale skin. Callidora's stomach turned as she looked at the branding, and again as she remembered that for most of her life she had longed to see her arm baring this sign of loyalty. Dumbledore slumped as though all the energy had left his body but his voice still held rage as he spoke. "How did they do this?" he asked her desperately. "He only just returned."

"Bellatrix had it done before he came back into power. Over Christmas break I met him." She shuddered as she spoke remembering his unhuman form. "To him I was proof the he could still gain followers, so he agreed to mark me when Bella asked." She admitted all this to him easily hoping, that if anything, he would appreciate her honesty.

"So now what?" the Headmaster shot at her as he stood and began pacing his office. "You want me to find a way to reverse it? You know as well as I do that can't be done."

"I am aware of everything this mark means, Headmaster!" she snapped at him, before calming herself. "I am not asking to undo it. I am asking how it may be of help to you."

He stared at her with wary disbelief so she continued. "I am a coward who cannot live with what I have done or what I will have to do if I follow the path my family has laid down for me." She made this statement calmly, and continued, "The only way I could live with myself now is by helping you in your mission against the Dark Lord, and I would like you to inform me of how I can do that. I'm sure there is something you can do with my…" she looked down at the mark, "connection."

The headmaster seemed to recover from his momentary shock. "As grand as what you are saying sounds, you have to realize that help offered by a Death Eater is not help I usually trust." As much as she understood what he was saying the words the Headmaster spoke still hurt Callidora.

"Of course I understand that." She reassured him weakly. Callidora felt like giving up this wild idea of hers right now, but she knew what sort of life lie ahead of her if Dumbledore turned her away. "What can I do to prove to you how sincere my offering is?"

Now, the Headmaster spoke with the tone of man with power. "You must agree to be questioned by me under veritaserum and with the use of legilimancy, all proctored by someone I trust. We will question every detail of your life, and every intention you have towards us. Only then will I decide whether or not to accept your offer." His tone was cold, but the words he spoke warmed Callidora's heart.

"Yes, of course I will agree to that," she rushed not even trying to hide her happiness.

"Tomorrow at eight, then," stated the Headmaster "Keep in mind I can always decide your loyalty resides in the wrong place, and you know the consequences that will befall you if I do." She did, though she had been desperately trying to convince herself that even being kissed by a dementor, was better than staying at Voldemort's side. "Go now, and I will see you then." Finished the Headmaster.

Callidora followed his orders thanking him as she rushed out the door, running directly into Snape. The head of her house glared down at her and she hardened her eyes to hide any emotion from him. Snape was a Death Eater. She hadn't wanted to believe it until she saw him, briefly, standing at the Dark Lords side at a revel. This was the reason she had to get McGonagall to set up her meeting with the Headmaster, she didn't want Snape relaying that information back to his master. Now, Snape brushed past her coldly into the office.

Callidora was left alone in the hallway with only her thoughts. She took a few steps away from the door before slumping against the wall. If she were a weaker woman she would have cried, but Callidora was raised to be numb to emotion. Despite this, sudden happiness rushed through her because she had survived this meeting, and its incriminating confessions, but it was tainted by the dread of what was to come tomorrow.

She knew that it was crazy for the Headmaster to even give her this chance considering she had recently declared her loyalty to the person he was fighting, and she tried to focus on this small win. The truth, however, was that here was no way Dumbledore would be so accepting towards her tomorrow after he saw what was in her mind. In his defense, she wouldn't trust herself either.

The momentary high of not being put on a criminal trial yet had faded and been replaced by gnawing nervousness, and on top of this she had to pretend everything was normal. Running into Snape had been a harsh reminder of the fact that she was just going from one hell to another, because now she had to return to Slytherin. So, she forced her expression into her classic slytherin bitch face and prepared to act indifferent. It was Friday night, so maybe, if she was lucky the common rooms would be in the middle of an end of year party by the time she got there. This way she could drown her fears in a bottle of firewhisky and the toned body of a slytherin prince.

…

Severus' bones creaked as he sat down in front of Albus. He was not an old man, but his life had taken its toll on his joints and his psychological health. He didn't want to waste this time telling Albus things he already knew, since Severus knew he didn't have any new information to report. All he wanted was a glass of wine and to be alone but the headmaster insisted on these little visits. He tried to think of ways he could defer the conversation from the fact that Voldemort had not been confiding in him recently.

"What was little Black doing in here?" he questioned after remembering their run in in the hallway. He was never fond of the girl because he was fairly certain that she had no mind of her own. From what he could tell she was merely Narcissa and Bellatrix's plaything. Not be mention she held an uncanny resemblance to his childhood tormentor. Though she was not blessed with the height normally possessed by the Black's, her hair fell in the same unruly waves as her brother's, and her face bared feminine versions of his handsome features. Despite his dislike for her, his interest had been peeked when he caught her sneaking out of the headmaster's office looking very shaken.

"She has been marked." Seethed the Headmaster and Severus' teeth began to grind together on their own accord.

"Impossible," he snapped "He has only just returned and everyone that arrived that night were people he marked before his fall. The girl was not there." Severus refused to believe that Voldemort had been claiming students without his knowledge.

"I saw the mark, Severus. Bellatrix made it happen, it is no lie." The headmaster stated solemnly.

"How did you find out, then?" he asked. "What, did she tell you herself or did one of her Slytherin friends betray her?" he couldn't stop the sarcasm from dripping from his voice.

"She did tell me actually," admitted the Headmaster. "That's we need to talk about." Severus felt sudden dismay at the Headmasters words. How had the girl managed to catch him off guard twice in the span of minutes?

"She came here and offered her help," the Headmaster continued, "and I intend to accept it. If the circumstances are right of course."

"If the circumstances are right? What in the name of Merlin does that mean?" Severus asked, thoroughly enraged by the Dumbledore's illusive language and even more so by his own confusion. "None of this makes any bloody sense. Why would a newly marked young death eater effectively incriminate herself for the chance to help the light side?" he questioned.

"That is precisely what I intend to find out tomorrow when I question her under veritaserum. If I find her trustworthy that is where you will enter and employ legilimancy on her and we will decide where to go from there." The Headmaster explained this in the hard voice he saves for when he really needs to lead.

"Me?" asked Severus, "She can't know I work for you. It is very likely the little brat is just following the misguided orders of some young death eater she fancies. There is no other explanation for why she would do this." By now Severus was nearly seething at the idea of having to be a part of this situation at all.

"Like I said, that is what I intend to find out. Also, Severus, you will be glamoured beyond recognition so there is no way you are getting out of this." Dumbledore scolded. "You know that either way this goes it will involve you, but I know that this is not an easy situation to handle. Nobody wants to be faced with sending their student to death, as you will have to if she is not sincere." He knew the Headmaster was trying to be understanding but for some reason Severus found no comfort in his words.

"That is very true." Severus conceded. "If you don't mind I will be heading to my rooms now." He got up as quickly as his joints allowed and stalked out the door just in time to hear Dumbledore instruct him to be back at seven the next day. He didn't bother answering as he was already half way down the stairs.

Severus could fell a headache forming behind his brows and knew it primarily stemmed from confusion. None of what the Headmaster had told him made any sense despite what he tried to tell himself. He was very certain this girl was a puppet, and he refused to accept that this new development made that any less true. And now the stupid child had him in angry fit instead of somewhat relaxed as he normally would be this close to the end of the year.

"Tiresias." He muttered as he reached the door to his rooms. The irony of his current password hit him as he rid himself of his cloak and flopped into his leather chair. Tiresias the blind prophet of ancient Greece knew everything before it happened. Usually Severus felt a degree of connection to this level of intuit, but tonight he felt nothing but left in the dark.

Eventually he had to resign to accepting the unknown, with only the comfort of knowing that it would all come to light tomorrow.

…

Authors Note:

*Please Read*

Thank you for reading the first chapter of my fic. This is the first one I have ever written and I hope it's not too terribly awful. For those interested I thought I would include some facts and dates and such on this story. I tried to make it as close to canon as possible but I had one big overlook that I will explain later. First of all according to the actual books Snape would be born in 1960, making him 35 years old during The Goblet of Fire, which would have taken place in 1995 considering the final battle at Hogwarts happened in the year 1998. Since 1995 is Callidora's final year at Hogwarts she presumably would be 18 meaning that she was born in 1977. As stated earlier she is the younger sister of Sirius Black. Since she was born in 1977 Sirius would have been 17/18 and already disowned. Two years after her birth their father Orion would die at age 50 and Regulus would die at age 18. When she was seven her mom Walburga would have died at age 60. This seems very old to have such a young daughter, but wizards live longer than non-wizards so I'm hoping it isn't too weird. After her parents death I had her primarily being raised by Bellatrix, which is where I made my big mistake as Bellatrix would have been in Azkaban for most of Callidora's childhood. But, considering I'm completely making up a character I figured I could change that detail too. Anyway, since there is an eventual relationship between Cali and Severus I thought I should point out that the age gap is only 17 years. To me that doesn't seem like a huge deal, but I guess if it is to you than you don't have to read this. I would also like to mention that I have no beta to proof read these for me so feel free to point out any mistakes you see. Also, a fair warning that the rating on this will likely change from T to M for sauciness and other more dark subjects. Sorry this note was so long, but thanks for reading it all if you made it this far. I would love it if you left a review.