This is a prompt fill for the wonderful canibecandid on Tumblr. It was getting too long, so I've decided to cut it into two parts. The second one is half-way written, so it shouldn't be too long before I post the end. To all of my lovely Sherlolly followers (which is all of you, I think), this will eventually be a Sherlolly story, but it's more of a Molly x Irene story. Fair warning: Sherlock doesn't appear in this chapter at all.

That being said, this is probably my favorite thing I have ever written. It's taken a lot out of me emotionally, so please give it a read and tell me what you think!

Disclaimer: I own nada. Rated T for language and sexual references.

Who can say if I've been changed for the better?

But, because I knew you, I have been changed for good.

XXXXX

Irene Adler meets Molly Hooper on a Thursday, one week after her fifteenth birthday.

Molly stumbles into the small clearing on the outskirts of the school grounds, stopping when she sees Irene sitting there. Irene quickly swipes her eyes to hide any evidence of her crying. Irene never cries (At least not where others can see her).

Observing Irene's distressed state, Molly walks over to the other girl and plops down beside her. She pulls a handkerchief from a pocket in her jacket (a bright pink and green concoction that looks like a unicorn coughed it up) and hands it over. Drawing her knees up to her chest, Molly keeps her gaze forward, giving Irene some semblance of privacy to pull herself together.

"Why did the person fail the cadaver lab?"

Caught off guard, Irene turns towards the shorter girl. "Huh?"

"He just couldn't cut it!"

Molly giggles at her own joke, the sound of her laughter infectious. Irene can't help the chuckle that escapes her lips, although it sounds more like a half-sob to her ears. She takes a deep breath. "That was…." She can't really come up with a proper descriptor.

"Bloody awful, yeah, I know. But it was supposed to make you laugh, so it worked, you see!" Molly smiles brightly, a ray of sunshine on an otherwise dreary afternoon. Gazing at her out of the corner of her eye, Irene grins in response.

Shifting closer, Molly bites her lip. "Listen…. Are you alright? I heard what those other girls said to you back there…."

Irene waves her off. "Yeah, I'll be fine. It's just…."

"Fuck them," Molly replies, so calmly that Irene wonders if she misheard. Only the slightly pink tinge to Molly's cheeks gives away that she hasn't. Irene decides then and there that she quite likes Molly Hooper. The two teenagers lock eyes, a silent understanding passing between them.

"I'm Molly, by the way," she continues, unnecessarily. She holds out a hand.

"Irene."

XXXXX

Their friendship blossoms rather quickly after that.

To anyone else, the relationship doesn't make sense. While Molly is shy and tries to blend in with the wallpaper, Irene loves being noticed by everyone. Irene prefers to study politics and the intricacies of social interactions, but 'Morbid Molly', as she is known by their peers, favors chemistry and anatomy. Irene knows what she wants, and how to get it. Molly is content to sit back and see what happens. They share no common interests, other than an apparent distaste for their fellow students.

To the pair of them, however, none of those differences matter. They are two outsiders, brought together by chance. ("Fate," Molly says one day. But then, Molly's always been the more optimistic one.)

Molly takes it upon herself to make sure Irene finishes her classwork, occasionally forcing the dark-haired beauty to sit down and study. Irene, in turn, drags Molly to a variety of parties, dances, and the like. She teaches Molly about confidence ("Nothing is more attractive than a woman who knows she's amazing. Remember that, Molly."). Molly shows Irene that sometimes acting weak can be a powerful weapon ("Make them underestimate you, Irene. It gives you the element of surprise.")

The first time Irene lets Molly borrow one of her dresses and fixes her hair in the latest style, interested boys flock to the petite girl, and she spends the entire evening occupied on the dance floor. Irene just smirks at the joy on her best friend's face.

Later that evening, they are lying on Molly's bed, fingers interlocked as they face each other. Irene listens as Molly waxes poetic about Colin, the first boy who had asked her to dance. Molly is detailing how green his eyes were as they stared into hers, and Irene feels an unfamiliar twinge in her heart.

She feels like she's losing something she never realized she wanted to begin with.

XXXXX

Irene Adler realizes that she prefers sex with women when she is seventeen.

Molly Hooper is the first person she confides in.

Instead of the shock or horror she is expecting (And, even knowing Molly as well as she does, she still expects one of those reactions), Molly embraces her, squeezing her tightly. She listens as Irene confesses her fear that her parents won't approve, and that she'll be disowned when they find out.

"Fuck them," Molly states quietly. (Those two words have become a mantra of sorts, shared only by the two of them.) "Where's the confident, sexy Irene that I call my best friend? She doesn't give a damn about what anyone else thinks." Molly beams up at her, grasping Irene's hands between her smaller ones.

And just like that, Molly calms her worries. Her heartbeat stops racing and her breathing slows. (Molly Hooper accepts her as she is. Who cares about anyone else?) They spend the rest of the afternoon talking. Molly asks thousands of questions. How did she come to this realization? When is she going to tell her family? How will she come out to the other students at school?

"Is there any special girl who's caught your fancy?" Molly teases, brushing her shoulder against Irene's.

"No one in particular," she replies, a devilish smirk crossing her lips. "You know me, Mon chaton. I like to keep my options open."

It's the first lie she's ever told to Molly Hooper.

XXXXX

Molly and Irene surprise no one when they announce they are going to the same university.

Of course, the gossipmongers rejoice over their living arrangement. The girls opt to rent a flat together, a small two-bedroom five minutes from campus. Whispers follow them throughout their small town, rumors of their not-so-secret love affair passing between the townsfolk. Molly just laughs and rolls her eyes.

Molly's mum takes them furniture shopping, and Molly radiates excitement as she puts her arm through Irene's and pulls her through the shops. Irene tries to keep an air of casual indifference, but doesn't quite manage.

On the way back home, Molly and her mum are singing along to the radio, loudly and slightly off-key. Irene gazes out the window, the sky a mixture of pink and orange as the sun sets. She glances over at Molly, energetically mouthing into a hairbrush as the song swells.

Irene doesn't think she's ever been happier.

XXXXX

Molly and Irene acclimate to university life fairly easily.

They quickly fall into a routine. Most days, they grab a quick breakfast and then make the short trek to campus. Molly chooses to study chemistry and biology, while Irene focuses on psychology and political science. After class, they grab takeaway on the walk home and spend the rest of the evening finishing up any coursework.

Molly finds a job working part-time in her biology professor's research laboratory, while Irene discovers that her aptitude for persuasion can be very profitable when used on the right people. If Molly disapproves, she says nothing.

Fridays, however, are Irene's favorite day of the week. The pair of them stay home, Molly curled up on the sofa with the latest fantasy novel, and her glasses perched haphazardly on the tip of her nose.

Irene sits beside her, pretending that she's watching the television and not the way her best friend sighs in happiness when she reads a particularly fascinating passage.

Sometimes, they stay up until the wee hours of the morning, talking about nothing and everything. Eventually, Molly falls asleep nestled into Irene's side, her breaths raising goose bumps on Irene's skin.

XXXXX

Things change drastically, like they always do, during their final term.

Molly has just been accepted into medical school, and Irene couldn't be any happier for her.

She takes Molly out to their favorite pub to celebrate, and the small woman gets a little too excited, downing three shots before they've been there fifteen minutes. After the second time she barely manages to catch Molly from sliding out of her seat, Irene decides it's time to go home.

Irene retrieves their coats and ushers Molly out the door. The night is chilly, and Molly huddles closer for warmth. Despite the cold, the sky is perfectly clear, stars illuminating the city streets as they stroll back to the flat. Molly occupies herself trying to identify the constellations. Molly's always been rather giggly when she's had too much to drink, and tonight is no exception.

"There's the dog, Irene! Do you see it?!" She points up, cackling and blinking her eyes. Irene suspects her vision may be a bit blurry at the moment.

"Sure, Molly. Of course," she says, humoring her pissed flat mate. Molly continues to babble until they're back in their small flat. Irene sits her down on the sofa and fetches her some water.

Molly gulps it down greedily, not noticing when some of it drips down her front. Irene sighs and leads her to her bedroom. "Time for bed, Mon chaton."

Molly groans in protest before clumsily reaching for the hem of her shirt and trying to remove it. It becomes stuck around her head, and Molly's arms flail around helplessly until Irene takes pity on her and assists.

Once she is safely in her pajamas and sitting on the side of the bed, Molly grins goofily up at Irene. She reaches out, grabbing Irene's hand and pulling her down so that the two women are at eye level, Irene kneeling on the floor. Molly leans forward and plants a quick, chaste kiss to Irene's lips. Irene gasps out in reply, drawing back slightly so she can stare into Molly's brown eyes.

"What…?"

"I love you, Irene," Molly whispers so softly, Irene feels the words more than hears them. "You're my best friend. You know that, right?" She gazes at Irene earnestly, her bottom lip jutting out. Irene finds her expression absolutely adorable.

"Of course, Molly. You're my best friend, too."

Molly smiles and lies down, her soft brown curls fanning out against the pillow. Irene stays on the floor until Molly's breathing slows. She shakily stands up and marches to the door, pulling it shut behind her.

She leans one hand against the outside, gently stroking the dark wood. "I love you, too, Mon chaton," she mutters quietly before heading to her own room, the sweet taste of Molly still on her lips.

XXXXX

Irene begins distancing herself from Molly after that night.

She goes out frequently, spending more and more time in the underground world in which she is creating a name for herself. (They call her The Woman, and Irene pretends she doesn't notice the jealous glares the other girls shoot her. She lifts her head and saunters off.)

Sometimes, she stays out all night, ignoring Molly's frantic text messages.

Where are you? – Mx

Are you alright? – Mx

Have I done something wrong? – Mx

Call me when you get this. – Mx

Please. – Mx

Molly finally confronts her, one Friday the month before they graduate.

"You're heading out again?" Molly questions, blocking the door as Irene attempts to slip past her.

"Yes, Molly. Now, if you'll excuse me, I don't want to be late." She reaches behind Molly to push open the door, but Molly stands firm.

"But… it's Friday," Molly retorts, failing to hide the hurt in her voice. Irene refuses to make eye contact. She doesn't think she could stand to see the disappointment in those brown orbs.

"Yes, I know." Her tone is biting, as if by wounding Molly she can ease some of her own heartache. (It only causes her more.) "Please, Molly," she says quietly, her shoulders sagging.

"Oh, okay." Molly's eyebrows scrunch together in confusion as she tries to make sense of the situation. Irene knows that Molly has no idea of the anguish she is causing. She puts a hand on Molly's shoulder, a simple gesture meant to bridge the gap between them, expanding every day.

"Let's have a girls' night tomorrow. How about it?" She grips Molly's chin between two fingers, her blood-red nails looking luminescent against the milky skin there.

"Al-alright. I suppose so." Molly's attempt at a half-smile falls flat, but Irene doesn't say anything. Instead, she brushes past her flat mate and out into the hallway. She waits until the door closes before letting out a deep sigh.

XXXXX

Irene takes out her frustration on her client, a married businessman with a ruddy face and an atypical taste in extramarital activities. (Irene never mentions that his wife is a client as well.)

He is currently cowering before her, wearing only a pair of thin cotton trousers while Irene strokes her favorite riding crop lazily across his cheekbones. Sweat trickles down his body as he stares down at the floor. Irene spares him a disinterested glance.

"I believe that's all for today. You may leave."

"Y-yes, Mistress." He scrambles away, breathing heavily, though Irene knows it isn't out of fear.

She grabs her phone from the table, perusing through the photographs she had taken during the encounter. Bright red lips light up in a sinful smirk as she saves them. One never knows when such things would become useful.

A sudden prickling at the back of her neck has her on high alert, and she quickly closes her phone and locks it. Lifting her head slowly, her gaze comes across a slight, well-dressed man leaning casually against the door frame. Although she's never been one to believe in good versus evil (There are far too many shades of grey for the world to ever be that black and white), Irene thinks that Satan himself would fall at this man's feet.

When he notices her attention, his mouth quirks up in a Cheshire cat grin. He meanders towards her, taking his time as if he knows she won't move away. (She won't. She is far too intrigued.)

He takes her hand in one of his, and she is struck by how small he actually is. He carries himself with such confidence, clearly accustomed to being the center of attention. It's a feeling Irene understands well.

Pulling her hand to his mouth, he presses a delicate kiss to her knuckles before releasing her. Irene remains motionless, keeping her eyes locked with his. She has the uncanny feeling that he is testing her, waiting for her to break eye contact first. His eyebrow lifts minutely, and Irene mentally pats herself on the back. This man is clearly not impressed easily.

"Yes, you will do nicely, indeed. How would you like to work for me? Put those… talents of yours to a more lucrative use?" He holds out his hand this time, allowing her to make the next move.

She grasps it firmly between both of hers. "Irene Adler. But most of my clients know me as The Woman."

"Moriarty. James Moriarty."

XXXXX

Molly Hooper and Irene Adler part ways for the first time on a Sunday.

Grey clouds block the sun, giving the day a gloomy air reminiscent of the day they met. It was rather cool for May, and Molly wears a brightly patterned jumper (pink and green, just like that first day) to combat the chill.

A black car pulls up to the pavement in front of their building, and Irene dons her favorite coat before turning to look at Molly. Tear tracks mar Molly's normally rosy cheeks, black lines of make-up running from her eyelashes to her chin.

"I thought I demonstrated the importance of waterproof mascara, Mon chaton," she chides softly, cupping Molly's face. The other woman sniffles, brushing her tears with one hand, although they are quickly replaced with more.

Molly mumbles, "Y-you d-did." She gazes up at Irene through watery eyes, pleading with her to stay. "Y-you don't h-have to go, Irene." Her words are a ploy, one last attempt to convince Irene to change her mind.

"I want to. I need to. We've discussed this many times, Molly."

"I know. It's just… we've been inseparable for so long. I don't know how to be myself without you anymore." Irene hides the way her heart clenches at the confession, wanting to surrender to Molly's gentle appeals. Instead, she tightens her grip on Molly's cheeks and gives her a sad smile.

"Do you know why I call you Mon chaton?"

Molly draws back slightly in surprise. Obviously, that is not what she was expecting to hear. "N-no. I know it means 'my kitten.' I looked it up once. I assume it has something to do with my being harmless and friendly all the time." Irene sighs and closes her eyes. Opening them, she presses her forehead to Molly's so that the shorter woman has no choice but to stare directly at her.

"Molly! I want you to listen very carefully, because what I am about to say is quite possibly the most important thing I will ever tell you. Okay?" At Molly's slight nod, she continues. "I call you that because, while you seem meek and cute, when riled, your claws come out. It is the most fascinating phenomenon I have ever witnessed."

Irene takes a deep breath. "You are the strongest person I know, Molly Hooper. You don't need anyone, me least of all. You are going to attend medical school, earn your degree, and become the country's top forensic pathologist. Do you understand?"

Instead of answering, Molly's arms wrap around Irene's waist as she clutches desperately to her best friend. Irene understands how she feels. They have promised to keep in touch, but this feels more like a goodbye than a new beginning. Their relationship has been irrevocably altered, and Irene mourns the loss of what they once had.

Before she regrets it, Irene pulls away, kissing Molly's temple briefly before striding towards the car. She turns back once more, committing the image of Molly to memory. The two women smile at each other, and then Irene pivots, sliding into the passenger seat.

It is this vision, Molly's hand raised in a silent goodbye as tear drops trickle onto the pavement, that stays with Irene for the next five years.