Disclaimer: Tsubasa Reservoir Chronicle belongs to CLAMP. I'd have put in a space arc.
Warnings: Stalking, romantic feelings
Pairings: SeiSub
Continuity: Set sometime after the Acid Tokyo arc.
Prompt: Originally intended for either the "Futuristic" or "Scifi" prompts of different Tsubasa Chronicle Months, but i didn't finish in time, and then they stopped holding the event.
1.
The generation ship has been travelling through the stars for close to two hundred years. The people on board have never stepped onto the surface of a planet. They have no knowledge of soil beneath their feet, or a snowflake landing on bare skin, the silver light of a full Moon cutting through shadows, or standing on the edge of a mountain with the wind in their hair.
It's a strange world to Kamui. Probably more to Subaru. Kamui hasn't asked. All that matters to him is that the ship's records have no indication of a Seishiro matching the hunter's description anywhere on board.
Of course, they have no records of the twins, either, and they have to scramble to explain their presence. Kamui leaves that kind of thing to Subaru. His older twin has always been better at dealing with people.
Kamui prefers to prowl through the ship, ensuring that there will be no problems and that Subaru will be happy here for however long they stay. It's the least he can do, knowing it can't be long.
There are maybe a thousand, maybe up to fifteen hundred humans on board the generation ship. Some worlds the twins have been to, that would make up a large city. On others, a tiny town barely worth noticing. There are faces Kamui recognizes, and more that he doesn't. It doesn't matter – he doesn't care for humans like his brother does. The only reason he cares if he recognizes someone from a previous world is that it makes them easier to read.
It's not as though the hunter or his brother is here, after all.
That's all Kamui needs to feel comfortable in a world, but Subaru is guilty over coming to a place with such limited resources. "It's not as though we eat their food," Kamui points out.
"Yes, but we take their blood, and they need to be able to make up for it," Subaru replies. "We shouldn't stay here long."
So be it. It doesn't matter to Kamui where they go, so long as they remain safe from the hunter. Once they've rested, they'll go. In the meantime, Subaru can play nice with the blood-sacks and help them however he is able.
ii.
Ah. This world is no good after all. Seishiro had such high hopes, when he learned about a Subaru with black hair and green eyes and a twin.
But this twin is not Kamui. It's a girl, almost a mirror image of Subaru, and her brother is not a vampire.
Seishiro has lost interest. He's considered the benefits of claiming other iterations of Subaru, but it's meaningless if it's not his own Subaru.
"Get away from my brother, you creep!" the sister shrills, lunging for him. Seishiro parries her without a thought.
If the vampire twins aren't here, there's no point in lingering.
Seishiro casts a wistful smile at this world's Subaru, who seemed ready to invoke some kind of spell in his sister's defense but now blushes prettily. Seishiro shoves both siblings from him, away so that they won't be caught up with him when he opens the way between worlds. He has no desire to spend more time in their presence. He finds the very idea revolts him.
"I'm sure there is someone in this world who's looking for you," he says, and then he is gone.
3.
Kamui has to be careful when he picks out his prey. Even moreso than on other worlds, due to the close quarters of the generation ship. He doesn't dare cause a scene which might put Subaru in danger.
This world is very frustrating – he's already ready to leave. But Subaru still wants to linger, so Kamui has to put up with it. He doesn't know what his brother is looking for.
He doesn't consider the possibility that Subaru is intentionally dawdling in the hopes that his hunter will catch up with them. That's impossible; even Subaru has some sense of self-preservation.
This girl doesn't, and Kamui is happy enough to take advantage. Her name is Miyuki, and for some reason she's popular with the female officers. Kamui can't see it himself, but she's easy enough to lure away from watchful eyes. The girl is a born mark, all too willing to follow a predator like him into a supply closet.
He doesn't bite her in the throat. It's too easy to kill that way.
Kamui has had to adjust his feeding habits since he started running with his brother. Though they are siblings, they rarely took their meals together – it isn't the way for vampires. Kamui thought nothing of killing his prey when he's finished with them, but Subaru doesn't like it, and so now Kamui has to be careful to leave them alive.
It's just as well. In a limited space like this, it would be hard to cover up a series of dead humans, drained of their blood. This way it's easier to hide, but at the same time it means he has to feed more often.
Subaru has been feeding like this all along. Kamui wonders how he can stand it.
He's always been too kind for his own good. Not like a vampire at all.
That's why Kamui has to protect him.
On the flip side, it's not easy to hide a rash of humans with anemia and puncture wounds in their wrists and elbows either. Kamui is already overhearing concerns about a malfunctioning machine, or some kind of space pest that's gotten in somehow, or a disturbing new trend for the young people. Kamui encourages the confusion when he can, downplays it when he can't. They can't linger much longer.
iv.
The next world is barren – plants and animals, but no humans. No vampires. Seishiro is able to sense, now, with his supernaturally heightened senses, whether he will find prey or predator anywhere within his vicinity. He can tell this world is useless to him, and so he moves on as soon as possible.
Once again, the vortex opens around him and carries him through spacetime to another place, another time.
He lands among a bank of computers. Seishiro recognizes them, although they aren't native to his home world. He's seen all kinds of wonders on this hunt.
None as wondrous as his chosen prey, of course.
Computers can be very useful. If you know the right codes, you can pull up a vast web of information.
If he can access these, they will tell him if there is a Subaru in this world, and quite possibly if it's his Subaru as well.
A quick glance at the keys tells him it will never be that simple. The characters used are entirely unfamiliar to him. It's not the most difficult language he's come across – he recently passed through a world that records its history and government documents entirely in a complex system of knotted cords – but he has neither the time nor the inclination to sit down and puzzle this out.
Not when it would be so much more sensible to find a local and make them talk.
5.
Subaru has ideas in his head about how to help, as he always does, and so Kamui is forced to follow him down into the engine room.
"The thing is," Subaru says, "i don't see how an artificial vessel can continue to run for centuries, without magic being involved. Even then, the ship's mages would have to be constantly using a great deal of energy to keep it going – but the officers all swear they do no such thing."
"So?" Kamui asks. "If you try and adapt the engines for magic, they won't be able to keep it going after we leave. And it's not like either of us knows a thing about machinery."
(He's lying. Kamui knows a little about engines, after spending three years in Tokyo. If a hoverbike broke down out in the wastes, either you fixed it or you were dead. He'd adapted.)
"I know – I just want to see," Subaru replies. "There's no such thing as a perpetual-motion machine, and if they think this is, it will lead to problems in the future. I want to see what's going on so they can be prepared."
Kamui rolls his eyes. He doesn't let his twin see. "If you say so."
The engine room should be busy; all their experience on technologically-oriented worlds says so. To power a ship this size, there should be all manner of things that need doing, by dozens of engineers.
There aren't. The engine revolves without human interference, with only two humans around to monitor it in case of emergency. No one Kamui has heard Subaru talk to can imagine any kind of emergency arising with the engine, and the two staffers are certainly no exception. They're very young, hardly more than children, and engrossed in deep conversation. The boy is leaning very close, almost – but not quite – touching the girl's hand.
It's revolting.
Kamui hopes very much that Subaru's plan is to slip past the two of them unnoticed, rather than talk to them and try to get permission to get close to the engine. Indeed, that's exactly what Subaru does, and Kamui follows him swiftly into the engine compartment. The young monitors don't even notice.
The engine turns, grumbling quietly as it feeds power into the rest of the ship. It makes less noise than Kamui expects, even in this confined space surrounded by smooth walls. "That doesn't seem right," he admits – his first acknowledged concession to Subaru's mystery.
"No, it doesn't." Subaru steps closer, lays his hand on the frame. Kamui hovers over his shoulder in case the engine tries to take his hand off.
According to Yuuto, Satsuki was the best with engines of the people in Tocho. Anything mechanical seemed to love her, would do whatever she asked of it. Kamui wouldn't know. She was the only one with anything resembling medical training, and so far too valuable to send out into the wastes. Kamui interacted with the rest as little as possible.
Maybe she would know what they were looking at here. Maybe Yuuto would, or Kusanagi, or Nataku. Kamui does not.
He's quite sure Subaru doesn't, either, but he examines the machinery with a curious air. "That's not the only thing that doesn't seem right," he observes. "Look at this – right here, it doesn't seem to connect to anything. And here, too. The engine is turning, you can see where it feeds power out, but i can't tell how the power is generated. And there's no connection to feed fuel in."
"Didn't they tell you it doesn't need fuel?" Kamui points out.
"Yes, but this . . . i don't think it's possible. It's like a child's drawing of an engine, it doesn't look like it should actually work."
"And yet, it does."
Subaru ignores him, reaches out to lay a hand on the casing of the engine itself. Kamui grabs him to pull him back, but there is no accident. The machine slows under Subaru's hand. Kamui looks around, half-expecting the lights to falter, but they don't.
Subaru digs his nails into a fine crack and flips a panel open. Despite himself, Kamui crowds closer to look over his shoulder.
He knows what he's looking at. So does Subaru. Neither of them says a word as they stare at a glowing white feather, marked with a script neither of them understands.
Subaru closes the panel. The engine starts to turn again.
"Sakura-san will have trouble with this," Subaru observes, breaking their moment of silence.
"Will she?" Kamui replies. "She didn't seem to mind leaving a feather behind to protect the people in Tokyo."
"That's true," Subaru says. "I only hope it won't come back to hurt her."
Kamui is reluctant to agree with him, though only on principle. Getting emotionally attached to the people they meet on their journey will only hurt his brother in the long run. (And it is the long run.) He doesn't have anything against Sakura herself, but he resents Subaru's concern for her.
The two of them leave the engine room. There's nothing they can do about this.
vi.
In these cramped confines, Seishiro learns of a pair of brothers, twins, who simply appeared one day out of nowhere, not that long ago.
He also hears of a spate of anemia among the foolish and trusting.
He bares his teeth in a predator's grin. Finally.
7.
Someone has been asking about them.
About them specifically. About a pair of mysterious twins who appeared as if out of nowhere. Mentions them by name. Asks about the anemia, too.
There is not enough fresh hot blood in all the humans on the ship to relieve the chill in Kamui's flesh. He presses for a description, and gets one.
A tall man with broad shoulders. Short black hair. One eye is visibly glass. Dressed in black with a white collar.
The hunter is here.
Right here. Kamui sees him step out from behind a bulwark. He smiles. "Hello, Kamui."
No. No, no, no, they haven't even been here that long, how can he have caught up with them?
Kamui has to find Subaru.
No, he should kill the hunter before Subaru finds out he's here.
But he's tried that before, and Seishiro is stronger than he looks. Moreso now, now that he has Subaru's blood in him.
Kamui bares his teeth unthinkingly. He would love nothing more than to tear that man to shreds. He's not sure he can do it without attracting Subaru's attention. Not in an enclosed space like the ship.
And if Subaru gets involved, he will try to protect both Seishiro and Kamui. Try to stop them from fighting and make peace instead.
There can be no peace with the hunter who got his hooks into Kamui's twin brother.
Running it will have to be.
If Subaru finds out the hunter was here, he will never forgive Kamui.
It doesn't matter. Kamui has made up his mind. Even if Subaru hates him for it, Kamui will protect him this time. He'll put his own will above Subaru's wishes.
He has to find Subaru.
viii.
The trail is hot.
Seishiro moves faster. He starts to run without realizing it. They're here. His vampires, his Subaru, are here. They are in this world, and he's in this world, and he will catch them at last.
Deal with Kamui. Claim Subaru for his own.
Kamui is ahead of him – Seishiro can't quite catch up with him, but it doesn't matter, Kamui isn't the one he wants to catch up to, and he will lead Seishiro to Subaru.
Kamui tries to lose him. Seishiro stays on his trail.
It's the closest he's ever come, in the years since this long hunt started.
He sees them. The vortex swirls around their bodies, ready to snatch them away to a world where he can't touch them. Kamui is using his body to block Subaru's view, the bastard, looking over his shoulder to see that Seishiro doesn't come too close.
But it's that moment of distraction that proves his undoing – Subaru shifts, just a little, and then he sees.
"Seishiro-san!" Subaru stretches out a hand, but Kamui's arms are around him, holding him in place, preventing him from going to Seishiro.
And Seishiro is running, but it's never going to be fast enough. Before he can reach his vampire, both Subaru and Kamui wink out of existence.
A/N: Was craving vampire fiction, and also thinking that CLAMP haven't done much in space, so i wrote this.