He is more nervous than he should be, standing outside Lungbarrow in the evening light. Quences has this no visitors rule, and it might be conspicuous if Theta quite plainly disappears, and they'd be tracked down in fifteen seconds flat. The punishments are not pretty.

Then he gets an idea.

Koschei walks to the front door, TARDIS more or less disguised as an oak tree (as per Oakdown tradition he has a hard time breaking), eyes still bagged from the night and formal robes still on. They're proper Time Lord robes, too, fancifully embroidered at the lowest rank possible above Juniors. You can judge a person's rank from the approximate time it took someone to sew the damn thing.

He knocks on the door. Four times. Just for fun. Someone he doesn't know opens the door, looking at him oddly, and at his clothes. Their eyes look a bit too small for their circular face. "Can I help you?"

"Hello, I'm looking for a certain Theta Sigma. I'm a professor from his old Academy and need to make a copy of his final qualifying marks for our records. We tried contacting him, but the only version of him in the matrix we found was an offline account linked to our school's issued slate."

The cousin is young enough to believe him. "Okay, sir, I'll go get the Housemaster, um…" she starts closing the door.

"Can I come in?"

"Oh yeah, sorry." He steps over the threshold, closing the door behind him, and realises just how much he knows about the layout of Lungbarrow. And how far he'll actually get when Quences walks out and sees a very obviously just graduated Prydonian in front of him. He could just yell for him to come down, but it would also bring a number of cousins and Quences a bit too fast. Walking around knocking on doors wouldn't work, either.

And Quences, it seems, has gotten a facelift. "Who are you?"

"Hello, ma'am. My name is Professor Varek, I'm from the Prydonain Academy. Theta Sigma," he says it like he's only heard it once in his life, "used to attend. We need his final marks for the first attempt at Time Lord exams for our records."

Quences folds her arms. "I used to teach there, you know. I don't remember this being a part of protocol. Can I see your credentials?"

Koschei laughs, just once. "Sorry, ma'am." He holds out the psychic paper he 'borrowed' from some seventy-year-old at least six years ago. It's all the rage nowadays, apparently. "This procedure was added only seventy years ago, as there were few cases of this occurring. However, the gaps in our records were great enough, administration decided it was necessary to follow up on the few cases, for completion."

"That's fine, but if you checked properly, you would have noticed the death record." Koschei doesn't see the small cousin scurry away.

He grins despite himself. "Our procedures are very thorough. This article proved to be a forgery."

"Oh, well then." Quences shifts her weight from one foot to the other. "Forty three percent."

"What?" She looks up at him. "Pardon?"

"That was his mark. You can go home now."

"I'm afraid I'll have to see an official record of that. What with the legitimacy errors of the death certificate."

"Well excuse me. Come this way."

Koschei is escorted down a flight of stairs and into a grand office-slash-residence. The best part is that she probably knows Koschei is holding up psychic paper, but she can't say anything about it in case it actually isn't. His alibi could be dismantled in less than a minute very easily, but in the slim chance he's telling the truth, Quences simply can't.

In the time it takes her to reach the computer and start uncovering files, Koschei tries finding Theta's mental imprint without letting much on. She's not allowed to comment on his mind anyways, he's a professor, that would be rude. Theta's here. He can sense something like an individualised shoe or the top of his head: it's him, it's definitely him, but it's not quite all of him.

He missed Theta.

"Here you are, then. Sir." Quences shows him the computer screen. "Marks for every question, forty two percent."

Koschei nods. "It pays to be thorough." Or something. Theta's getting closer. Is he a good enough telepath to figure out he's here? No… "It would be most efficient to send this straight to the Academy files form your computer, if I may do so."

"What are the other options?"

Koschei mentally kicks himself. He's impressed he even got this far. "On occasions where this is impossible, we may use a portable drive. However, it's very easy for these things to be corrupted or damaged early on."

Quences stares at him, throwing up Koschei's mental walls instantly. He smiles charmingly.

"Go ahead, then."

Theta is right behind him.

"I brought Theta Sigma down."

"You did what?" Quences is not looking at Koschei. He can get away with clearly not sending it to the Academy now. "Into my office?"

Theta sees him. He can tell without looking.

"Look, you made up a death certificate ten years ago, and now you're talking about him as if he's alive about his own education, he has a right to know."

Theta doesn't respond. It physically pains Koschei to not look up, to focus on the task at hand, to figure out how to make it look like he exported a file.

Theta doesn't speak, but Koschei can hear his breathing, and everyone notices this.

"Are you okay?" the small cousin asks Theta.

"Hmm?" he chokes after a while, voice a little gravelly. "Yes, yes. What's going on here?"

"I'm professor Varek," Koschei tells him with a smirk pointed at the computer, "from the Prydonian Academy. I'm here to get a record of your," he presses a few buttons and returns to the screen the file was on, finally allowing himself to look up. It looks like Theta's been gone for three hundred years, not ten. "…marks." What the hell did he miss. "You are, in fact, Theta Sigma?"

Theta looks at his body. "Yes."

"Yes," Quences adds.

"Sorry about the body, it's… a long story." Theta looks back up at Koschei, unable to suppress a grin despite the old, old face. Koschei has another brilliant idea.

"On the topic of stories, I'd also like to interview you. As it happens, there are very few in-depth records of House-schooled people, and we'd like to ask some questions about education and about life learning from home. The information will help optimise teaching structure at the Academy. Would you be up to that?"

"Yes," he answers a little quick.

"The questions are a bit long for this hour. However, will tomorrow work? Perhaps in the neighbouring city for a change in atmosphere?"

He looks to Quences, as if for permission to take her son away. The woman can't say no, even if it's painstakingly obvious she knows. "I don't see the harm in that."

"Fantastic. Say, 09:00?"

###

Theta is handed a jar full of goldish pills as soon as he walks in the door of a very obvious statue of a whale, and doesn't quite know what to do with it. The nervousness in his stomach will not stay down. He thinks the nerves all come from having an old man's body where it should be young and dexterous. For example, he wants very much to kiss Koschei for a long time, but doesn't know how that's going to work with all the… skin.

"Does it ever hurt you, being old?" Koschei sits on the railing around the control panel, looking tired. He's changed out of the formal robes into just a t-shirt and pants, hair still dripping water on occasion.

Theta closes the door. "When I try doing things I really shouldn't be doing. Like running." He unscrews the lid of the jar, taking out one of the pills. It almost pulses, swimming around in its casing.

"I've been out here for a few days, working on those. I'm older than you."

"Weren't you already?"

Koschei waves a hand in dismissal.

"Is that regenerative energy?"

"Yes. I finally got it in a solution. The research took me to many interesting corners of the matrix."

Theta sets the jar on the floor. "How much?"

"Take it first."

"How much?"

Koschei draws in a breath. "One life."

Theta almost drops the pill.

"It'll reverse the effects of ageing for about a month? I think? I was on all these cosmetic resources and they all said different things and I'm pretty sure one involved some kind of drug I didn't have on hand."

"You put an entire life into this jar."

"Yep." There's only a teeny part of him that regrets it. Mainly for the existential crisis it put him through. "Swallow it. The effects begin within twenty seconds. Or forty-five. I haven't tested it."

"It's just that easy?"

Koschei snorts. "Depends on how you want to define 'easy'."

Theta puts the pill in his mouth with shaky hands, tremors from God knows what plus the old bones. He keeps his feet planted just inside the door until he feels the slightest burning tingle course through his body, scrubbing away the age and put life back in him. His muscles have shrunk significantly. "Better now?"

Koschei slides off the railing and holds out a hand. "So do you want to chat now or later?"

Theta twines his fingers in Koschei's, filling the artificial ache of separation from years ago.

"I seriously hope 'chat now' was a joke."

"I am physically and psychologically restraining myself in every way."

Theta smiles sideways. "Just to find somewhere comfy?"

"I feel like we'll be there for a while."

###

"I am finally here."

"And in costume, no less."

Theta has almost reverted back to the enthusiasm of a child, dressed in a poor boy cap and only somewhat rickety clothes, complete with Koschei's gloves with only half fingers from That Time On Obraeon.

"Sol III. London, England, 1940," Koschei announces in his best attempt at professionalism. "We're stuck on relative time, so no more than three hours out here. Or else they'll catch us."

Theta nods vigorously. Koschei opens the door. Theta just about knocks him over on his way out, running very conspicuously into the street, but he obviously doesn't care. Koschei does the normal thing and walks. But only barely manages it.

"Where should we go, then?" Theta asks, practically bouncing up and down in the dank street with an odd smell. The sky is shockingly blue as compared to Gallifrey's sort of orangey yellow hue. Theta runs over to mostly green grass before Koschei has a chance to answer.

"You're the expert on Sol III, I'm only the pilot."

Couples in frilly dresses and battered suits give them funny looks, the pair running around a single street marvelling at the state of everything. "Well, we need to try the food, that's obvious. And walk around and blend in with the people and look at the shops. And there's this river right in the middle of the city they can even get horses across and the river's just there they can't do anything but sit in boats on it. Yet."

Theta runs over to the nearest available homo sapien, who looks slightly uncomfortable. "Excuse me, ma'am, can you tell me a good place to get food around here?"

She looks Theta up and down, the boy vibrating with excitement, deciding him too predisposed to weirdness to bother much with. "There's a place for lunch just up the road that way," she nods behind her. "Can't miss it. They got a live singer in."

"Koschei! She says there's one just up the road with a singer!" Theta shouts without moving at all, and the lady briskly walks away. Koschei runs over to Theta's spot on the sidewalk. "Have any money?"

"Of course I do." He holds out a handful of blank coins. "Psychic currency."

"How do you have that?"

Koschei shakes his head. "Ten senior years at the Prydonian Academy."

Theta counts five men in matching uniforms, the real-life versions of people drawn on posters around the room saying things like "support our troops" and "enlist". There's a war going on, which Theta probably should have known, because it clicked when he got the menu this was the second World War, so it was a pretty big deal. He ordered the Shepherd's Pie, mostly out of curiosity as to why they would serve a dish normally intended for shepherds in an urban area. Koschei got the French onion soup, wondering equally as hard why they would serve a French dish in a very English restaurant. Or "club", as he heard someone say.

Theta leans over the table slightly. "So these people are all in a war, getting bomb threats every other day and running into shelters."

"And?"

"And here they all, even the soldiers, sitting together having lunch and listening to someone sing 'with all your faults, I love you still'. None of them are so afraid it shows." Theta takes another bite of shepherd's pie, refraining from throwing his fork down in satisfaction. "It's bloody fantastic!"

"Theta!"

"I'm allowed to say that word in England."

Koschei bursts into small chuckles at everything. They're on Sol III, eating oddly-named food, listening to someone sing, with a bomb threat hanging over them and the rest of the population.

"What?"

Koschei would like the recipe for French onion soup, but is far too afraid to ask lest it be out of place. "You're brilliant."

Theta lets his legs dangle over the edge of the TARDIS into space, only after multiple promises the gravity will pull him back in if he falls. Koschei sits next to him, in the same position, occasionally eyeing him in case he leans over too far and does, in fact, fall off.

The Medusa Cascade is painted in light green and blue and orange, like a constant stasis of their leaf fires. The rift slices through the most dense centre of clouds, temporal sort of gravity pulling them in until the horizon cuts it all out. It's a bit terrifying, the rip in reality, especially when nothing but space and clouds (and a functional gravity field) separate you and it.

Theta tells Koschei a very long word.

"What was that?"

"What my mum called me." Theta extremely carefully budges over the small bit enough to lean against Koschei. The Medusa Cascade is now a bit sideways. "She always sang the full thing when I was a kid. It was the first two syllables when I got in trouble."

Koschei looks at him, then at the rift, then simply returns the favour. "But I like yours better."

"More vowels."

They sit in silence for a moment, watching the beautifully slow process of cosmic dust moving about a rift.

"So what spurred that motivation?"

Theta kicks his feet just a little, creating a ripple in reality itself. Nobody will notice the disruption of a couple of shoes. Or maybe they will. "On the twentieth day of the last month, a woman showed up in my backyard. Her hair was done fantastically in some pile of knots. Had a patchwork dress of fabrics from who knows how many systems. The shoes were bright blue with a white star on the ankles, didn't look too sturdy." Is it messing in the space-time continuum if he obviously reveals her identity? Should he mention the oak tree? How much detail does he want from him? "She told me to describe her to you in detail. She seemed to know what she was doing."

"I'll keep that in mind."

Theta shifts his head on Koschei's shoulder, crossing their legs out in space.

"You know, the first time I had marshmallows at a camp fire, my cousins forgot I was there, and I got knocked out in the middle of the night."

Theta pauses halfway through a roasted marshmallow before continuing. "I do not remember you telling this story."

"They had some huge bonfire, and didn't have any water, so I volunteered to go get it. Something started chasing me so I ran for my life, got knocked out, and woke up in the morning with a giant empty bucket."

"So you didn't get eaten."

"I did not get eaten. They probably had the place cleared of all lethal fauna long before I got there."

The jungle below has probably not been cleared of lethal fauna. But whomever's abandoned village this is, they were high enough up the technology tree to run an electric net around their elevated property. It's still comfortably spooky without much sunlight to illuminate their safety net, but nothing a campfire and marshmallows on top of a jungle tree can't fix.

"Do you know who lived here?" Theta asks, cold enough to require a blanket on his sturdy, wooden platform. The firepit is, of course, stone.

"I think they called themselves the Trepids, habitants of Intrepida. They had all the technology down pat, but naturally evolved to value nature a whole lot more than most sentient species. That's how you have tree dwellings and electric katanas designed to shock a creature unconscious first, and kill it humanely after."

Theta lights one of his marshmallows on fire, taking his time in blowing it out. "Who booted them out?"

"The Pteronites. They kept preaching about the apocalypse with enough compelling evidence to get them all underground and therefore into slavery."

"And they're still there?"

"I don't know about enslaved, it's been a while, but for all they know the outside world is a burnt husk."

Theta chews his marshmallow, furrowing his eyebrows, looking to the canopy of stars for permission as he always must. "Should we go down there and tell them?"

Koschei points his marshmallow stick at Theta. "They figure it out themselves, one day. A purebred Pteronite, revered by his peers, the one guy who got everyone equal rights in the end. If we mess it up now, we'll probably get things thrown at us and they may never live in peace."

"And here we are using their firepit."

"In the middle of a thousand galaxies all hanging out. Not once has someone painted a dead accurate picture of this sky."

"I bet Mort would try."

Koschei snorts. "He'd be here for years."

###

Koschei wasn't there when Theta woke up in the morning. Not in bed, not in the kitchen, not in the wardrobe, not in the console room, not anywhere. He tries mentally scanning for just another brain in general, but he's not good enough to find someone that way. He tries suppressing the boiling panic in his head, claiming it's only being accustomed to having Koschei constantly present for over a year and half now.

Maybe he's parked outside a grocery store or something to restock the kitchens. Yeah, that's probably it.

Theta's hearts still make an unnecessary amount of noise when he walks up to the console, and he hesitates before opening the doors. Nobody could have gotten in here; it's a school vehicle. Locked beyond comprehension. Theta takes a deep breath and flicks the switch to open the doors. Outside their pocket dimension are a smattering of trees, sprouting from messy red grass. Gallifrey. They look vaguely familiar, but then all the trees on the planet are mostly the same.

Theta runs a hand through his hair a few times to make it look halfway presentable for any people he might run into, taking a chained key off the console and looping it around his neck.

He strides out the doors, into the barely-there canopy. It's very intentionally organised, and the trees can't be very old. "Koschei?"

No response. He locks the door behind him. It is ten steps of walking before the Deja-vu algorithmically increases into the answer dangling just above his head. He just can't place it.

The trees thin out after ten steps more, and he runs the rest of the way, half-expecting an Academy to appear at an awkward angle before him. He stops once he sees the building clearly. It's Lungbarrow. Did Koschei just turn them both in? It's 5:00. Why now? Why at all?

Before he can get much closer to the front doors, Koschei comes running out of them like he's on fire.

"Shit!"

"What the hell are you doing?"

"Run! Now!" Koschei grabs him by the hand, pulling him back the way they came.

"Koschei, what did you just—"

"I'll explain when we get inside!"

Small branches whap him in the arms and the face, Koschei's hand is too tight, they're running too fast, and someone is actually chasing them. It's Glospin.

"You better have a fantastic explanation!"

Koschei doesn't reply, ripping a key off from around his neck and jamming it in the lock of their obviously misplaced oak tree. "Come on, come on…" he grumbles, slamming the door open and pulling Theta inside before Glospin can reach them.

Koschei leaves Theta inside the door and immediately runs to the console, jamming all the levers and buttons to start moving without punching in coordinates. The machine lifts off the ground, out of space, into the vortex.

Koschei, clad in all black and even painted charcoal in places, slides to the ground, heaving breaths.

Theta tries not to stomp over to him, but some could describe it like that, standing with his arms folded a bit too menacingly for their day and age. "Explain?"

Koschei can only meet his gaze for a second, eyes needing to regain their determination, and he holds up one finger.

"No, now. Where do you even start?"

Koschei steels himself, trying to make eye contact with Theta again, failing, and compromising on a spot on his forehead. "So we've been stuck here, right? Not… not at the House, but in relative time in short hops. So they don't notice something."

"Yes."

"And you had to stay at your House for the last ten horrendous years."

"Yeah."

"And because of that, Glospin had you alone to try and use that… laser thing." Koschei still doesn't stand, still hasn't regained his breath. The charcoal on parts of his face has started smudging. "And because of that, I put one of my lives in a jar."

"You didn't have to—"

"No, I did."

"I don't see where this is going."

"Wait. I'm almost done."

Theta shifts from his right foot to the left. He doesn't drop the folded arms for a lack of anywhere else to place them.

"You don't want to get married, but you have to for some bullshit reason."

"We've been over this…"

"You don't have to."

Theta swallows, trying to find a complete explanation. "I don't get it."

Koschei takes a deep breath, letting his head tip back. He finally makes eye contact. "Quences is no longer with us."

Sorry, no, "What?"

Koschei exhales the shuddering breath he held in. "I killed Quences."

Theta sits on the floor across from him. He blinks a couple times, picking at the cuticles of his fingernails and trying to form a coherent thought. "You just… went in and…" his wrist makes circles in the air that beg for words to be procured. "Killed him. He's dead. Gone."

"The rank of Housemaster will be passed down to Innocet, as it turns out."

"Innocet."

Koschei nods very shallowly, trying not to twitch the wrong way and set off a bomb.

"She won't make you get married. Quences was on his last life, and from what you told me, artificial. Her ideals were too outdated, and we could have avoided all the trouble of the past ten years without her."

Theta nods once, twice, biting his lip to see if sense comes from there.

"We can leave whenever you want."

Theta stops nodding. "What's wrong with you!?"

Koschei's back straightens, all breath regained. "Look at the pros and cons. She was near the end of her life, and keeping you—"

"No, no shut up."

Koschei shuts up.

"You don't know anything about why Quences did what he did. And he talked to me, over those past ten years, he'd help me with schooling, you can't just—" Theta, in all his shock, can feel the threat of tears in the sides of his head for the old man he thought he hated. He stands up. "It was my mother's life, passed down to me, that I gave him to regenerate! I let him live and THIS IS WHAT YOU DO?"

Koschei still shuts up. He holds out hope Theta's argument might loop around. But he can't see any other way it could have worked.

"I WOULD HAVE BEEN FINE. Quences would have died on her own time, I could part with my House on decent terms, actually pass my exams, get some life experience and now you're expecting me to run off with a murderer!?"

The word stings, fired through the ear canal and exploding in the corners of his synapses until his whole mind resonates with the current reality. He is a murderer. But then, hasn't he always been?

"If you murder people to solve your problems, I'm a dead man walking."

Koschei has to speak. "If she was on her third life, there's no way I would have killed her!"

"But you did! You had every single possibility laid out in front of you, so many of them lacking death and full of a few better ideas that would get us past these barely-done developing brains and whatever else, but you decided nah, this person is clueless, better fucking KILL THEM HOW LONG DID IT TAKE YOU TO THINK THIS THROUGH? Or was it some spur-of-the-moment decision, like Vansell in the closet? You'll probably kill him, too!"

Koschei stands. "You hated those ten years. You hate being stuck, you nearly I because you felt so pointlessly STUCK, and here you're saying you'd rather be a hell of a lot more stuck than do what we've been planning to do for a hundred years!?"

Theta puts two hyperactive hands on Koschei's shoulders. "YOU…" there is a moment, spanning two overactive breaths, where he sees his fork in the road. It dissolves a little quicker than he wishes it would. His voice will not turn down below his horrid shouting. "I met you less than a minute before you bludgeoned someone to death with a rock at the age of seven, and before any part of our lives began, we burned the body. Since day one you have been completely past fixing and now I fear you'll kill me in my sleep!"

He finds the audacity to smack Theta's arms off. "I KILLED QUENCES FOR YOU, WHY THE HELL WOULD I KILL YOU?"

"BECAUSE YOU'RE FUCKING INSANE." Theta shoves Koschei off of him, deliberating his own spur-of-the-moment ideas, all of them interrupted with a well-trained fist on the jaw. His teeth slam into his upper jaw, pain shooting up his skull and pulsing in his jawbone ceaselessly. But it wasn't hard enough to make him bleed. It wasn't even that hard. But his brain cannot rationalise this fact.

"You see what I mean?" The portion of his consciousness that has began cooling is screaming and crying and begging him not to go. "You keep your jar of life. If you step out those doors, I'll turn in the ID of this TARDIS without hesitation."

"Theta—" he says, watching the doors open and Theta turn towards them. "I'm sorry."

Theta barely makes it through the doors in heated blood and a cold chuckle, all ends of his mind screaming at him to walk one way or the other, or maybe just stop and think.

He considers it for an entire two seconds.

No, he has a funeral to attend.

Some estranged fourth argument forces him to stop, and turn on one foot, and look back into the TARDIS. Koschei has not moved, the muscles of his jaw clenched so hard against his teeth, his face looks pained. But he didn't try turning Theta around with his brain.

"Thank you," Theta says. What for, he doesn't know.

A/N: If anyone out there can name the 3 other nations corresponding to Pteron, I will give you the most over-excited internet hi-5 ever.