A/N – Okay, I know what some of you are thinking. What kind of sick perv keeps having these sisters get so naughty. Though, I've stopped to defend myself for a moment here. Let's think of how many animes this is so common in. Utena for example with Anthy and Akio. Marmalade Boy, though Miki and Yuu only believed themselves to be related. Candy Boy has two sisters very clearly in love. I could go on, as there have been many more over the years, but as you see, if I am crazy for this then at least I'm not the only one. Besides, they're just so damn… cute. Now, on with the angst!

As for the plot, consider this kind of Auish (only slightly) since though I've seen the anime I'm kind of combining things from the games that I've read on and also just making some stuff up. It's fiction made from fiction. Just enjoy it.

PS- ChupaChupa says I'm just a perv. That may be slightly true as well. At least she still betas for me. XD

Girl Disappearing

By: Azfixiation

xxxxx

As the days passed I continued to avoid Sakura as best as I could. I began to wake up early so that I could skip breakfast and just grab something on the way to school. Luckily our classes didn't match up, and it was easy to avoid her during lunch as we had grown into our own groups of friends growing up. At school everyone expected us to dislike one another, though neither of us had ever told anyone the cause of the tension. Though we had become closer during the grail war, we had decided to act the same during school as neither of us particularly wanted the added attention our sudden friendship would draw.

In an attempt to not be overly rude I made sure to always attend dinner at least, though that was also partly a selfish action as I truly did love Sakura's cooking. I tried to ignore the sadness in her eyes as she sat across from me. I know she wanted to talk to me, yet I wasn't ready to relent in my stubborn actions.

Well not completely, at least. After two days of completely ignoring her, the sadness in her eyes was even too much for me to bear and I knew that she hated herself enough for the both of us. Though not ready to go back to playing the doting sister, I did make sure to always stop next to her before leaving and kiss the top of her head before retiring to my room for the evening.

Though I spent most of my time thinking on it, I couldn't begin to think of a way to help Sakura. It seemed obvious, at least in part that I would need to find a way to kill or stop the remaining worms. But the reality was that though it would help her sexual desires, it would do little for her already abused mental state.

"Hey, Tohsaka, can I come in?" I hear Shirou call through my door and without awaiting my response I see him slowly opening it.

"Just because this is your house," I start sarcastically as I glare at him.

He holds up his hands in surrender before taking the chair at my desk. "I need to talk to you about Sakura," he starts off nervously. "I don't want to stick my head into your business but I don't think I'm really doing any good here."

"I'm sure she can look after herself," I say defensively, not wanting to have to talk about this with them.

"If you won't take care of her, at least tell me what happened so I know how to deal with it. She's practically obsessed with trying to bring Rider back and it's only gotten worse since you started acting like a selfish brat and began ignoring her."

His fevered tone put me on the defensive as I've never heard him speaking so harshly to anyone before. I rose from my bed to stand in front of him. "You have no right to accuse me of anything. We both know that what she's trying won't work and even if she could pull this off there's a slim chance she would even get Rider. Her mana is too unstable to do a proper summoning on her own, so if she wants to try let her."

"So, what? Are you just pissed because she's more worried about Rider than letting good old onee-sama take care of her?" I hear a new voice ask and before I even look I know its Illya standing in the doorway, no doubt eavesdropping.

"Who the hell asked you brat? Both of you need to just stay out of this. You don't know anything." I say in exasperation.

"That's why we're trying to learn. If you'd stop being so self-centered you would understand that we want to know what's going on because both of you are miserable. Who the heck wants to live with two miserable girls? Right onii-chan?"

Shirou quietly nods his agreement, and I realize I've been the one making a fool of myself. It is normal for friends to want to help, and by avoiding the situation and trying to handle everything on my own I've only made it worse for everyone. "It's kind of complicated," I say as I sit back down on my bed. "I'm not sure I can really tell you everything without Sakura's permission."

"Just tell us what we can do to help then," Shirou practically begs and for the first time I wonder if he cares more for my sister than I had thought. Illya nods as well and I know I have to at least let them in on some of this.

"There's not much we can do," I reply after a moment. "I wish there was but no matter what I do I can't find any answers. There are… things inside of her that control her mana flow and cause certain side effects. I've been looking for a way to purge them from her but I've come up with nothing. And even if I had the answer to that…"

I couldn't bring myself to tell them any more. If I told Shirou about her abuse he would certainly take off in hero mode to slay the rest of the Matou line. "We'll find it, right?" Illya said with a smile. "Three of us looking for an answer is better than one."

"Right," I say and though I feel awkward and dislike sharing my burden with the others their smiles let me know this is what they want to be doing. We are our own makeshift family now after all.

And so I tell them of everything I know about the worms and though I despise to admit it to them, I tell them of the adverse side effects they have on Sakura's sex drive. Illya gives me a scowl for putting idea's in Shirou's mind while Shirou blushes at the idea of a sexually charged Sakura. "If you even think about it…"

"No need to worry about that," Illya said as she reached up to drag him from the room by his ear.

With the burden eased, and Illya's words ringing in my ear of being self-centered I decide it's finally time to face Sakura. Assuming she even wants me around still. When I finally make it to her door I crack it just slightly to peek in but she quickly spots me and waves me towards her. "Onee-chan…" she says in surprise, quickly making room on her bed for me to take a seat next to her.

As I sit I chance a glance at her and notice the tears welling up in her eyes. I mentally kick myself for having caused her more pain than she needed. "How are you?" I ask awkwardly unsure if I should just pretend that everything is fine or if we should talk about things.

"I'm okay," she says as she smiles. I can't help but notice the smile doesn't reach quite to her eyes and though I want to hug her I'm also afraid of it having an adverse effect. One more glance into her sad eyes though and I can't help myself. I quickly envelop her in my embrace, holding her close to me and as soon as her face finds the crook of my neck her tears begin to fall. "Don't leave me onee-chan," she whispers against my skin. "I'm sorry I'm so broken. I'm sorry I'm mean to you. I'm sorry I... I… kiss you sometimes," she cries out as if at confession.

"I'm not going to leave you. I just needed some time to think okay?" I do my best to comfort her, unsure of how to proceed. "I just wish I could help or find a way to make it better for you," I confess.

"I'm sorry," she cries again, clutching my shirt as I keep her close to me. "I don't know how to control it. Before Shinji just… and it would go away for a while. I try everything I can and then it keeps coming back."

"Is that why you are so desperate to bring Rider back?" I ask, the implications causing me to blush.

Sakura also blushes as she nods. "She would come to me when she could and sometimes she would just be with me and sometimes we would…" she trailed off as the blush on her cheeks grew.

"You look cute blushing," I say as I run my fingers through her hair. "I hate to not be able to help you but you know you can't keep trying to summon her, right?"

"I miss her," she chokes out as she throws herself back into my arms. "She took care of me."

"Well we can take care of each other from now on, okay?" She nods against me and with a sigh I nudge her so she is laying in bed. "I'll stay with you but you need to sleep now."

Her tears continue to fall and I'm not sure if she was even listening to me. I let her stay close, her head resting on my chest as her tears begin to soak through my shirt. I rub her back to soothe her as best as I can, lost in thoughts of my own of how to help ease Sakura from her misery. I only hope the others can find a way to cleanse the worms. Quickly I place a kiss on the top of Sakura's head as she calms before I let myself drift off to sleep beside her.

--

Rin has somehow let herself fall asleep in my bed – not that I'm complaining. I can't begin to say how happy I am that she has forgiven me once again. Though as I take in our proximity I wonder if she has forgiven me too soon. Her fingers are lightly pressed against the small of my back beneath my shirt while her other arm is lightly draped around my torso.

I let myself nuzzle into her, inhaling her scent as I hug her close. The first thing I notice is that she is slightly softer than Rider, her muscles not as finely toned. I let myself reach up to play with her hair, remembering the days when my hair was the same such color and I vaguely wonder if it will ever return to normal.

As I settle back into her I quickly find my body more than happy to betray my desire to be normal. I repeat onee-sama in my mind as if it were a mantra, desperately trying to will myself to not desire what is forbidden. A part of my mind tries to rationalize all the reasons it would be okay, arguing that one could no more call Rin and I sisters than they could call Shinji my brother. A name did not make him family. Nor do the faint blood lines that flow through Rin and I, diluted by our years spent apart from one another as if we had not spent the first few years of our life together at all.

Yet here she is to comfort me, to hold me, which causes a surge of emotion to well up inside my chest. She holds me the way Rider used to, and though it is different it still resembles the embrace of a lover. With a blush I wonder about Rin's first kiss, silently hoping it wasn't me who stole it in such an ugly fashion. Reaching upwards I stroke Rin's cheek and press a chaste kiss to the side of her neck. "I'm sorry for feeling this way."

--

Sakura, who in her mind had every intention of letting herself drift off to sleep in her sister's embrace, found that her body once again wanted to betray her. As she shifted to get comfortable her hand accidentally grazed over Rin's breasts before resting on her side. Her fingers became curious as to what the flesh beneath her sisters shirt felt like, slowly working their way under the fabric so the pad of her thumb could trace small circles over the smooth skin.

The faint twinge of desire she had felt was suddenly ignited as she let herself push boundaries, her hand now sliding over the surface of Rin's stomach. Her hips were instinctively pressing against her sister, their legs having been entwined which let Sakura press herself against Rin's thigh.

Half wishing to beg Rin to wake up to stop her, and half terrified that Rin would wake up and stop her, Sakura once again lost herself in her desires as she tested the limits. Her lips once again found Rin's neck, this time though she let her tongue slide out to taste skin as she pressed gentle kisses along her sister's pulse point. Rin let out a small sigh of contentment, which sounded achingly close to a moan and before Sakura completely lost herself in her desires she quickly pulled away from Rin, practically jumping out of the bed.

She quickly moved to lock herself in the bathroom, tears streaming down her eyes at her inability to control her desires when it came to Rin. It frustrated her more so since control was never an issue with anyone else, and the prospect of her lacking control because of her emotional attachment to her sister frightened her. Torn between wanting to punish herself and relieving the pressure that had built between her legs, Sakura decided to do both.

Her hand quickly slid beneath the elastic of her pants, fingers deftly moving towards their goal. Once reached, Sakura's shame quickly washed away from her as always, the potent worms bringing forth her darker self as she brought herself to a quick yet satisfying orgasm as she bit on her bottom lip to keep herself from calling out her sisters name.

As she came down from her high, she found herself slumped on the bathroom floor, leaning against the wall. The shame and self-hatred was quick to wash over her and in a moment of desperation she found her hands reaching for a razor, her fingers quickly dismantling the plastic to reveal a full blade. She quickly lifted herself up enough to pull her pants to her ankles, and with a deep breath she sat back down and pressed the blade against the skin of her inner thigh. To remind me, she thought to herself.

Biting down on her lip she slid the blade in a painful arc against her thigh. She was desperate to remind herself that these things caused pain, not pleasure and had quickly decided that for every time she lost control, she would punish herself. One cut became two, which lead to three and four as she remembered the many times she had done awful things to Rin and found pleasure in them. As the cutting went on, Sakura watched the blood pooling from the cuts as they became deeper and deeper.

In her haze of loathing and desperation Sakura began to wonder if it were possible to cut the worms from her flesh, if somehow she could just dig deep enough to purge herself of the evils inside of her. Tear streaked and blood stained, Sakura dug the blade into her flesh in fervor, hoping and wishing for something, anything to stop the confusion in her mind and the pain in her heart.

She was unsure of how the cuts had migrated from her thighs to her stomach then to her arms. Cutting and prodding anywhere the worms could be, Sakura ignored the pain as she let her head fall against the wall, blindly marring her skin. It wasn't until her vision began to blur that she came to realize that perhaps she had gone too far. Or perhaps I have finally gone far enough, she thought as her vision failed her. She fell unconscious onto the floor, lying half naked in her own blood, strangely with the most serene smile that her face had ever held.