Extradimensional space is... funky. If one were to imagine a portal to another dimension being much like portals are often displayed, like holes in space with a weird glowy ring to constitute a border of where the hole begins and ends, then extradimensional space would be that exact line. Or at least, that's how it would look from the perspective of... materials. For those within extradimensional space, it is more similar to regular space in the conventional make-up than any self-respecting scientist would care to admit.

To explain it completely, dimensional travel would be akin to walking through a museum, and admiring the artwork displayed there. The walkways are your portals, you don't really interact with them, and they are really only built to get you from one painting to another, some paintings vary greatly, or could be much of the same. Some could be magnificent pieces of art drawn long ago, some could be simple glorified blotches of paint. Some of the artwork aren't painting at all, but statues or abstract statements. Like usual, interdimensional travelers don't tend to stay in one place. They have the option to go elsewhere, and will damn well use it. After all, if you aren't stuck in the painting, why bother staying in it?

Extradimensional space is none of that, it is the wall that holds up the painting, the floor below the statue. Always there, and there where the art isn't. It isn't so much like the walkways where they are there to facilitate the dimensions, but more like acting as a foundation that allows the art to be displayed to begin with. No one looks at the wall, no one admires the wall, and no one lives in the wall.

Well... that last part isn't entirely true, Esstrey is currently living inside the walls. She hadn't been needing to eat, because things don't exactly change in extradimensional space, so that bite she took from one of the squid faces? She still has bits from the calamari looking bastard drifting around in her stomach. The Goddess slapping her into this place, or rather out of real space? Yeah, she still feels a bit of a mark left behind by that nasty old lady.

Luckily, extradimensional space consists of a sort of semi-solid material. A solid that has much less density than water, so she is kind of feeling like that old duck from western comic books that swims through his ocean of coins. Or a mole that has found particularly soft dirt. The area does this without actually having any material there, just like space is vacuum in its base stage, extradimensional space is made out of the weird non-material. There is also some life here, usually in the form of fish or odd bugs that seem to ignore each other and Esstrey, but frankly a desert would have more life than this place.

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Esstrey did try eating some of the weird looking fish, but she couldn't pierce their scales. That most likely has to do with the whole 'nothing changes in extradimensional space' part, because it certainly didn't feel like the scales were too tough. Eventually, after doing some more tests on the fish, she let it go. It quickly swam off after that, and actually entered one of the dimensions. Which isn't particularly hard to do around here. The reason Esstrey hasn't entered another dimension yet? It's more of a matter of why she would rather than wouldn't. Most dimensions aren't looking too bright, or are looking a little too bright with their supernova's.

She did see a few that were vaguely familiar, one where she even saw her old mother Russia. She would have gone there... if everyone on that planet wasn't clearly eating the faces of others...

Unsettling corruptions of realities aside, swimming through extradimensional space is pretty comfortable, not to mention therapeutic. It kind of reminds her of the times it was her turn to clean up the barracks, calm sweeping while no one bothers you. Esstrey doesn't even know how long she's been here, time and distance are all very relative when you are quite literally not located on any maps.

Esstrey's calm swimming is interrupted by some sort of deep visceral rumbling, and as she looks around spots a massive worm circling her position. This would be the biggest life form she encountered by far, it must be the size of a whole building! And any creature capable of growing large in extradimensional space must be an impressive predator. Esstrey fires her massive crossbow at the worm, testing its skin.

Alas, the worm is as recipient to change as the smallest fish here, and the bolt deflects off of it like it's hitting a T-90. It doesn't even detonate, since the bolts used to rely on her mana to initiate any magical effects, and there is no mana in extradimensional space.

The worm doesn't appreciate the attempt regardless, and launches multiple... things at Esstrey. She deftly dodges most of the black tentacled projectiles, but one that would have been a near miss extends its sharp tentacles instead! It grapples Esstrey, and throws her off balance by sheer force of speed. Esstrey tries to throw the thing away, but it has embedded itself into her skin, somehow bypassing her scales totally. There is no evidence of damage being done to her, as if her skin is merely a suggestion when it comes to hampering its reach.

It quickly crawls over her head, and digs into Esstrey's upper spinal column. This isn't a predator! It's a parasite! Esstrey attempts to dig it out of her, but her skin works against her in the situation.

"Я сдеру с себя кожу и вырву твое сердце!" Esstrey talks big, but she's panicking. She has no way to deal with a non-material foe, but there is something she can do. She has plenty more experience in the material plane than the blasted parasite, so she will face it on her terms instead.

I will rip off my skin and rip out your heart!

Esstrey digs into the weakest looking barrier between her and real space nearby, speed is of the essence.