There was a hangar. Isara wasn't quite sure how she got there, but there she was. The only entrance seemed to be a great hangar door she woke up near. Lifting it up revealed a sort of… promontory. A long stretch of well-packed dirt with grass near the rims and not a thing more.

Inside the hangar was a lot more interesting. There was every machine and tool she could think of and several she didn't know, along will all the material she could ever want to shape. Billets and sheets of aluminum, a sea of screws and bolts…

It was like heaven. There was a dumbwaiter that handled her food and enough separated living room for two people. Two beds. If there was any issue, it was that: she had a feeling she should have had company of some kind. Squad 7 had… Squad 7 had…

She wasn't sure. For some reason, she felt like they'd be arriving early if they got here now. Still, there was a welcome distraction in work. She had enough notes, time, and resources to make herself a proper airplane. One with seats for two, of course. Because flying was something worth sharing.

There was a vague suggestion of an airplane's skeleton when she heard a rapping at the hangar door. Rushing over and heaving the thing open, she found herself looking down at a little girl. Blue-gray eyes and dark brown hair… she was cute. Maybe half Isara's age, if she had to make a guess?

"Hello?" The girl said.

Isara could handle this. Kneeling down a bit, she smiled at the girl. "Hello there. I'm Isara. It's nice to meet you."

"I'm Faye Yeager." The girl said. "Have you seen my big brother?"

"I don't think I have, but why don't you tell me a bit more about him?"

"Well," Faye said, her eyes lighting up, "his name is Grisha, and he's the coolest!"

Isara brought the girl inside and the mystery dumbwaiter provided lunch. She had been amazed the first time she used it – such abundance was a far cry from rations – and Faye was similar. She gorged herself between long rambling explanations of her life back home.

Problem: those rambles seemed to discuss another world, as far as she could tell. In addition to not recognizing Isara as a Darcsen (other than mentioning how pretty her hair was) she talked about a ghetto for a people called Eldians in a country called Marley. A country strong enough to have fleets of airships should be well known, at least to an aviation fan like Isara, but she had never heard of such a country, much less the people it apparently repressed. Maybe that was a sign of very efficient repression, but she thought she paid enough attention to the papers to notice something.

If that wasn't enough, the way she reacted to some of the Ragnite samples Isara was working with… "What's this, Miss Isara?" She genuinely didn't know about the stuff.

(Strangely, when Isara went to show Faye around the hangar, there was a door she swore wasn't there before. It led into a room with more notes, more parts, and pumps for something called gasoline. It wasn't quite Ragnite, but it filled a strangely similar niche.)

That had… implications for wherever they were, Isara thought. If she was from someplace where this Marley existed and where they utilized gas instead of Ragnite, one of them had either traveled to the other's world (was that much of a jump? She had seen world maps before) or they were in some sort of liminal space.

She really tried to think about how she got here, but all Isara could remember was a vague feeling of cold and someone singing… Isara decided against asking Faye if she remembered anything. If she got to thinking about the last time she remembered before the hangar, she'd start sobbing because she was parted from her brother–

Isara partially managed to distract herself from the bad feeling in her gut by looking after Faye. A young girl needed to be cared for, after all…

They ended up sharing a bed despite having two. Faye seemed to enjoy cuddling and being touched, but only when she initiated. That was another disturbing implication, but Isara did her best to stay open.

"You can rest your head on my lap if you'd like." Faye would lie down and Isara would talk to her while working through her notes. Faye was as excited by the prospect of flight as Isara was, although she really didn't have the means to accomplish it… well, other than by helping Isara out.

She was a clever girl, even if she struggled with fine details like measures and which particular screw or bolt to grab. Some of that could be explained by her being a child not used to that sort of work – Dad was a doctor – but Isara thought a slightly different system of measure might explain some of her difficulties.

"Where do you learn all this stuff, Issy?" Her newly earned nickname did not provoke the exact same emotions as Welkin calling her Is, but it was nice. It felt good to be looking after someone.

"Well, some of it was work with my father, the rest was me figuring out his notes."

"What was he like?"

"I've heard he was very kind," Isara said, attaching a sheet of carefully shaped aluminum to the airplane's side.

Faye frowned. "You've heard?"

"Yes. He died in an accident when I was young."

"Issy…" Faye went for a hug.

"Careful. Hugs are good, but I'm working with a tool."

"Sorry…" She stepped back, looking down at the ground with shame.

"Faye… I'd just like you to be careful." Isara said. "The last thing I want is you getting hurt before we go."

"Go… where?"

Isara smiled. "Well, that's the interesting part, isn't it?"

If y'all want a more serious crossover... I have no idea how it would pan out but who knows. Valkyrur and Darcsen, Eldians... maybe the setting could be a world where the Eldian Empire still exists?