Fate/School Days – Sidestory 03: Sakuya


Something was wrong with Karin.

Thinking back, I guess I started noticing it the first day she showed up after Rin-kaasan started the procedure to gradually transplant portions of her magic crest into my sister. Oh, Keiko didn't tell me, in fact I don't think she told anyone. I probably would have taken longer to figure it out if Mother hadn't told me herself. She couched it as an apology, as if she was sorry her own Tohsaka blood wasn't strong enough to give me any chance to be the heir to the Tohsaka branch of magecraft.

On the surface, it was completely irrational; Sakuya-kaasan had never had the chance to be formally trained before she had been given over to the Matou family, so there was no reason for me to expect such a thing. On the other hand, it was very much like Mother to apologize for something completely out of her control, which let me maintain my faith in reality long enough to puzzle out what was happening in front of me.

The first clue was that she had been walking quietly to school. Normally she would be bouncing around the three of us, striking up inane conversation, the latest gossips, that sort of thing. That day, she was hanging back slightly, walking at a steady pace with the rest of us. She responded and made comments to anything we said, but didn't initiate any topics herself. Koyuki was being more talkative than she was, which made me wonder if Grandpa Zel had tricked me through a portal into Bizarro World without me noticing.

Keiko noticed, of course, but she was concentrating on acting normal herself. I could see that the crest was already causing her body fits, if for no other reason than she was keeping herself completely under control, not betraying any involuntary movements. Keiko probably just assumed Karin was worried about her, like we all were.

School passed as usual. I didn't see my sisters until the lunch period, which also came and went without incident. The only point of interest was when Keiko tried to subtly open up a pack of medicine to pour into her drink without any of us noticing. We all noticed, of course, but pretended not to for her sake. Likewise, she knew that we had noticed, but acted otherwise. It sometimes made me wonder why we even bothered to put up with the pretense.

A few days passed and gradually Karin went back to normal. Back to the bubbly, hyperactive, teasing self she had always been; back to making our lives utter hell. And like always, we wouldn't have had it any other way.

ooo

The next week, however, Keiko stayed overnight in Rin-kaasan's study again. The following morning was a repeat of that one day, but slightly more noticeable. Keiko had one gasping the elbow of her other arm as she walked, as if bracing it. Karin was even further back behind us and quieter than usual. I saw Koyuki glance back a few times at her roommate, while Keiko continued walking at the front of our group, pretending not to notice.

Some days Fuuko-nee would walk with us. Normally this would mean a tag-team of two bubbly, hyperactive, teasing sisters prancing around us. Nowadays, Fuuko would often be walking side by side with Keiko, talking with her in low tones that I couldn't overhear. Occasionally the elder girl would look back at Karin with a rather smug smile on her face, at which Karin would scowl back at her, much to my confusion. Keiko and Koyuki would pretend to ignore the whole exchange, though I did sometimes notice Koyuki's eyes dancing between the two sisters.

I had plenty of time in class to puzzle it out, today's homeroom was self-study, which meant most of the class was engaged with conversation and other activities that had nothing to do with studying. For my part, I opened the teacher's slides for the previous day's lessons on my desk and pulled out my tablet and stylus as if I was going over notes. My stylus hovered over the tablet for a few moments, then without any prompting, my hand scribbled out a short note.

A fight?

I didn't often do this, but it was a better idea to let Yin have an outlet to express herself rather than completely keep her contained. Whenever I had tried that in the past, no matter how much self control I had, she would always break out at some point. The longer I kept a lid on her, the longer and harder she would lash out. In the long run it was better to give her shorter, more numerous opportunities, though as a rule I generally confined those to when I was around family. After reading her short note, I scribbled my own answer underneath her text.

Not on both of their parts. I didn't bother to expand on my answer. Yin knew everything I knew, she saw everything I saw. This was just a good way to sometimes get at an answer neither of us would consciously admit.

Keiko's ignoring everybody, Karin's just ignoring her.

Fuuko-nee?

Friendly. Friendlier?

I had to think about that one. Fuuko had always been a flirtatious sort of girl, both towards complete strangers and to family alike. Could she be...? I mentally shook my head.

Probably just trying to provoke a reaction from Karin.

She might know what's going on, though.

That was a good point. Find her during the break?

Yah. And also ask her about that one guy who keeps staring at your ass.

My what? I spun around suddenly, casting the last hints of movement as Harima-kun turned back to his circle of friends. There was a spurt of laughter from the boys as I cast a narrow-eyed glare at them, then turned back to my seat.

How do you see these things when I don't? I complained.

I know the ways of perverts.

Well, I couldn't argue with that.

ooo

Fuuko-nee was no help.

Well, she was, but in all the wrong ways. I glared at her in impotent fury as she held conversation easily with my pirated body.

"Well," the older girl was saying, "to me it seems obvious that Karin-chan is crushing hard on our sister."

"I still don't see why," my treacherous mouth was saying. "Keiko's always been eye-candy, but why now?"

"Sudden schoolgirl crush?" Fuuko asked rhetorically. She waved a hand flippantly, "Who knows why or when it happens. I admit that Keiko-chan does suddenly seem more... hm... delectable lately..."

"I don't see it," Yin said. "The only thing I can think of is that she's been getting her thommy – Thaumaturgical – thanks Yang, her crest thingy from Rin-kaasan."

Fuuko hummed thoughtfully. "You know, you might be on to something there. I'd have to see how far Daddy got in his research, because he's never seemed like my type. Yet at the same time there's just this quality about him..."

Squick. "Oh? What do you mean?"

Damn that Yin...

"I'd suggest asking Matsu-kaachan," Fuuko suggested. "She'd have a copy of all his research notes. But if I'm right, it probably has something to do with... us."

I blinked. "Koyuki isn't acting any differently," Yin pointed out.

Fuuko smiled, "Neither am I."

Somehow that didn't make me feel any better...

ooo

Asking Matsu-kaasan was actually an exercise in futility. In the first place, it was nearly impossible to find her. With the larger floor plan available to her, she had at least a half-dozen secret lairs she made available for herself. Normally the proper way to seek her out would be to go through Father – who could simply call out and she'd come running, or ask Karin – who had the uncanny ability to know where her mother was at any given time. Given the questions I wanted to ask, going through either of those avenues was not something I was quite willing to do.

I did try asking Koyuki in a rather roundabout way, but either she was too dense or I was being too broad in my questions, because I wasn't able to get anything more than generic answers to my very generic questions. The most I was able to confirm from her was that she had noticed Keiko and Karin acting differently. Unfortunately by the time I had worked up the courage to pose a more specific question to her, Karin had popped in as her usual, cheerful self and innocently asked me what we were talking about. I quickly dropped the subject.

The whole thing became moot point because like before, everything went back to normal the next day. There was still something about the whole situation that I couldn't quite put my finger on, but as the days passed without further incident it gradually slipped from my mind.