"Right. And, erm... What about money? I expect these things aren't literally for free unless I lucked out and got summoned to a post-scarce universe."

"The school's responsible for you since our students summoned you irresponsibly."

"Ah. ...happen much? They said there aren't protocols for meeting people from other universes and summoning was the only known interdimensional transit method..."

"No, it doesn't happen much, it's mostly a theoretical field."

"Is this world in regular contact with many others? Aaand what's it called, again, starts with an E...?"

"Not that I know of, and Elcenia."

He nods. "Well, er, I guess I shouldn't keep you with my million questions. Could you point me to the library?"

"Just ask the lift, it'll take you there. Same with the cafeteria, or the exit, or my husband's office - 'headmaster's office' - and if you need anything or get lost, just think 'Keo' really loudly."

"Okay. Thank you very much for your help and patience."

"You're welcome." And she gestures and says an untranslated word and vanishes.

Okay. So he walks into the room and looks around.

It's a double dorm room with furniture but no other objects. There's a window overlooking grassland.

...okay that's enough room exploration he will leave his stuff there and figure out how to lock the door and then go to the lift to pay the library a visit.

The door actually doesn't have a physical lock. It has a ward that responds to his intentions. Very userfriendly.

The lift works just as advertised and here's a huge library!

Eee huge library!

Okay first thing he wants to find out, because it's been bugging him, is length of year and month and week and day and seasons and what replaces hours and minutes and why not throw some stuff about the solar system in for good measure?

The calendar and time system are different. The planet is an only child, and it's square, and it orbits a sun, and there is a hemispherical moon which goes around the planet, and also there is air between all these objects.

What the. What the duck. What. What the.

"Excuse me," he finds the nearest librarian to ask, "but this book seems to think your planet is square."

"...it is," says the librarian. "Well, it's not infinitely thin like a mathematical square, I suppose it's technically a rectangular prism with mountains on top, but no one fusses with the details like that."

"H—how do—nevermind I'm sure this book will explain it to me, thank you."

How in heavens and in the name of all the gods does gravity even work. Why is it square. Why this. Why all of this.

Gravity doesn't. Down magic pulls toward the surfaces of the planet. And the flat side of the moon. But not the round side. It is speculated that there will be a down at any sufficiently large basically flat surface.

...so, what, if you're on the round side do you... what, what happens?

And how far is this moon anyway? And the sun? And what is the sun? And what is the moon? And who put them there? What about the stars?

If you're not near enough a flat surface you do not have a down, and float.

The moon is a long flight for a dragon or scoot but not completely intractable as a day trip for either. The sun is farther than that, it would take all weekend probably to fly there. The sun is a ball of fire and the moon is a rock and they have always been there. The stars are more balls of fire.

Aaaaaaaaaargh! Are the stars the same size as the sun and merely farther away, or are they actually smaller dots?

They are the same size and merely farther away. Well, about the same size, stars vary.

...what size is this, exactly? And how large is the square, by the by? And where do the oceans go? Is this tiny, tiny sun actually enough to warm the, er, planet? And are there, for that matter, other planets?