A/N: For anyone who's reading this to find out what's happening to the next chapter of March to the Empire, I'm still writing it! Really. I took a several month break, but I'm working on it, even though it's giving me a lot of trouble. That's what I get for abandoning it for so many months, I guess!

As you can see, I'm still writing. My other ongoing fics are also in progress-though slow progress.

About this fic: it always seemed to me that Matsuda felt hugely betrayed by Light, more than anyone else on the investigation team. I thought that this betrayal would have changed him, and this is the result. Please note that I haven't read the manga, only watched the anime.

Also, this is a one-shot. I have an idea for a completely different ongoing fic, but I've already got four of those and should probably finish at least one before I start another.

Now, without further ado: the story!

Later

Later, Matsuda pours over the information, trying to follow Kira's thoughts. Why had Light done this, and how that? It's foolish of him, he knows, but he'd lived aware of the fact that he might die for long enough—when he hadn't known the truth, he'd felt more confident, but now all his certainties are awash in a sea of blood, and it seems better to understand on his own.

Now, he is no longer Matsuda Touta, a naive rookie; the Kira case had changed him, changed them all, and this is recognized: all the Kira veterans are treated differently, afterwards. No one knows that their leader was Kira, of course...but it is known that their leader died in the final confrontation. People assume that it happened while he was trying to catch Kira, and don't mention it. Each of the men is quietly grateful, because they don't know they could have handled pretending that Light, glorious, hideous, deadly Light, was a hero.

Some years later, when the Kira case is just in police textbooks (it's amazing how quickly people forget, thinks Matsuda, and he can see the same thought in the faces of the other investigation team members whenever the subject comes up), it's due to this quiet status that none of them have to teach the basic classes. But there are some exceptional students every year, and these they do have to teach. It's tough work—but it can be interesting, watching the students pour over the information and come to conclusions, some correct, some incorrect.

None of them ever guess that Kira is Yagami Light, and this scares Matsuda slightly: it's as if Light's charismatic spell is reaching forward in time, preventing them from making even a random guess as to the real killer.

This year, there are more of these exceptional students than average. He's warned about one of them—Yagami Light, son of Yagami Sayu, who married someone with the same last name (though not, he finds out, a relation) and given her son the name of her brother, who she thought had died heroically. They say he's a genius, and he feels a bit of a shudder. He goes into one of the classes of Yagami (whom he tries, very hard, not to think of as Light), ostensibly because the teacher forgot to tell him something but really to see the young man, and feels more than a shudder.

Light and Yagami are identical.

He tells the others this, and adds that he'd like to teach the class with Yagami in it. They look at him, more quiet gratitude in their eyes, and he knows that they couldn't have handled it, and that they know it too.

He's warned about another student, too, but he's so focused on Li-on Yagami that he doesn't pay attention. He reflects, later, that it's his own fault for not paying attention when he nearly has a heart attack when one Ryuuzaki Ru, identical in every detail to the Ryuuzaki he'd known what now seems so long ago, steps into his classroom.

He reflects, too, on his use of the expression 'I nearly had a heart attack', because it's the first time he's used it, even to himself, since the end of the Kira case.

He pretends to wonder why he did so—but if he were to tell the truth, he'd admit to knowing why.

After the first class, Yagami and Ryuuzaki stay behind. There's a pause as they wait for the other to speak first, then Ryuuzaki waves Li—Yagami on ahead.

"Yagami-kun may go first," is all Ryuuzaki says, but there's a flash of anger in Light's eyes.

It may be because Matsuda has gone over the case again and again, (even though it isn't—can't be—the same person) but he fancies he can follow the logic behind it: Ryuuzaki gave Yagami permission to speak first, thus somehow implying a superiority.

Matsuda thinks that it's a good thing he's the first teacher with both of them in the same class, because he's not sure that another teacher could have handled it—though to be honest, he's not sure he can, either.

He thinks of the flash of anger in Light's eyes, and thinks that the Light he knew would never have revealed himself in such a way—but then, this one has never been a mass-murderer, hiding as the detective trying to track himself down.

And then he thinks that maybe the Light he knew would have, because Ryuuzaki got under Light's skin the way no one and nothing else did.

And then he thinks that it doesn't matter, because their not the same people, anyways.

And then he (who's seen shinigami and notebooks that can kill and cat-and-mouse games where both sides are the cat, who's seen a god die) wonders who he's trying to convince.

Then Light speaks. "Kira was Yagami Light, wasn't he?" It's not a question. Then he smirks, and adds, "My uncle, you know."

Matsuda knew, of course, but he still feels a moment of stark terror.

Ryuuzaki eyes Light suddenly, with a sort of cautious surprise. "That was the conclusion I came to, as well," he says, then brings out a cookie and eats it as Light's head practically snaps around in shock.

Matsuda knows it would be useless to deny it, and so tells them the truth. He also tells them not to tell anyone, though he's reasonably sure that the instruction was unnecessary. He writes them a note for their next class, fully aware that Light, at least, would be able to charm his instructor into forgiving him, though Ryuuzaki would probably just eat cookies and stare at his teacher until the fellow became too unnerved to continue admonishing him. He hurries them out of the door.

Then he collapses into his chair, staring blindly at the opposite wall for several minutes. He's aware that he's missing a meeting, but he also knows that there are other people from the investigation team there who will understand, and make his excuses.

It's half-an-hour later that he finally stands up, deciding to take the rest of the day off.

It's at that moment that he realizes that he's been calling Yagami 'Light' since he'd seen the flash of anger in the young man's eyes.

It's also at that moment that he decides to stop trying to do otherwise.

He searches the air around Light obsessively for the shinigami Ryuk for a week after that, and then gives up. If the shinigami comes, he'll come, though Light is smart enough to keep him away from any who can see him.

He still searches the news for reports of unnatural heart attacks in obsessive detail, though.

It's strangely amusing to him when he becomes Light's confidant in all matters Ryuuzaki, and thinks at first that the other Light didn't have a confidant—and then remembers that he did, and it was the shinigami. He wonders at first what that makes him, and eventually decides on sympathetic.

He's not sure how that makes him feel.

He does know how he feels when Light, in an unaccustomed fit of soul-bearing, tells him exasperatedly that he's the only one who understands the relationship between Light and Ryuuzaki.

Matsuda doesn't tell Light two things: the first, that he doesn't understand it, he's just seen it enough to have an idea of how it works.

The second, that there are others who might understand—but he never lets them meet Light, because he doesn't want to make his old teammates into murderers.

It doesn't come as a surprise when, a year later, all the old members of the Kira investigation team die of heart attacks. No one's put the pieces together yet, though he suspects that someone will, soon.

It does come as a surprise that, this time, Light respects him enough to meet with him in person before killing him. He knows it's time when he hears the knock on the door, even before he opens the door and sees Ryuk hovering over Light's shoulders.

He opens the door wide. "Please come in," he says, then heads into the kitchen. By the time the two get there, he's washed an apple.

He nods to Ryuk and tosses it to him—the shinigami catches it in his mouth, gulping it down in three bites. He'd changed his will, leaving all his things to Light, who he thought would be amused to find his cupboards and refrigerator filled with apples.

He motions Lights to sit down then, once he's done so, joins him. He looks the young man in the eye, and speaks.

"Light," he says. "If I might give you once last piece of advice?"

Light raises a slight eyebrow at this—he's surprised Light. Most of him finds it absurd that he's pleased to have managed it.

"Please do," Light says, with much the same gesture that Ryuuzaki gave Light a year ago.

"Keep Ryuuzaki with you," says Matsuda. "Friend, enemy, it doesn't matter—but alive. You want to win—he'll help you, keep you sharp enough that you won't fall for stupid tricks. Besides, you killed him last time—you know you can do it, now. This is a different challenge: can you keep him alive, still interesting you, without any evidence that it's you doing it?"

Light is struck by this; most people wouldn't see it, but Matsuda does. "Thank you," he says. "For your services to Kira, I will let you choose how you die."

This time, it's Matsuda who's surprised. He lets out a slight laugh; he'd never, in a million dreams, thought that this would happen.

"A heart attack," he says simply. Light nods, unsurprised, and reaches for his notebook. Matsuda does nothing to stop him.

Matsuda reflects, just before he dies, that he's unsure whether that last advice was real or sabotage.

He reflects further, just as darkness hits him, that if it is sabotage, his uncertainty is the only thing that might make it work.