Sid has given some thought to this scenario before, because it's the kind of thing that's fun to think about in the shower or while tuning out in class, but is not especially prepared for it, because making an actual like, serious plan for what to do if you get isekai'd to another universe is not an especially fun use of time. Oh well. How hard can it be?

First order of business: make contact with the locals. Most likely followed by a long and tedious process of pantomime to learn their language. He heads off in the direction of laughter.

The most convenient way takes him close to those ominous factories. He sees a metal sign declaring 'UNSAFE STRUCTURE' in a language that looks a little like Chinese but clearly isn't Chinese.

The people are over there! Looks like about a dozen of them, skinny dipping. As he watches, two ride a sled from the top of one of the hills, downhill, off a dirt ramp, and into the water.

They look sort of human, but a lot more like some kind of demihuman or humanoid creature from fiction. Their faces have what look like very short snouts, their legs are digitgrade and clawed, and they have long, furry tails and a light dusting of fur over their limbs. Their heads are more 'furry' than 'hairy', but somehow still quite natural looking. They're all incredibly thin and fit. Skin is mostly tanned, and fur is mostly a bright orange to white. They have pointed ears that twitch around in the kemonomimi style.

Oh nice, he can read the language. Hopefully speak it too. That's something to investigate in more detail later—ooh, animal people!

It would be nice to introduce himself with some humorous reference, but he has no reason to think they have any culture in common. Probably not a great idea to do anything that would startle them either. He approaches them and, once he is clearly visible to them, shouts "Ahoy!"

They scramble up into one group, chattering. One waves back. After a moment of conferral the one who waved calls, "Ahoy! Do you need something? You look off!"

Another shouts, "Where's your tail? How's the alien costume hiding it?"

"You're not going to believe this, but I'm actually an alien. I don't have a tail. I literally just got here, so I figured I'd introduce myself."

He continues to walk towards them as he speaks.

"Bullshit! What are you supposed to be, one of the makers?"

"He does look pretty weird!"

"Come over here and have a snack if you like."

"Take off those pants and prove your tailessness!"

"Guys, maybe we should-"

"Yeah! Off with the pants!"

A chant of pants-pants-pants then begins.

Well, he has no reason not to. Sid takes off his clothes, folds them, and sets them down on whatever moderately-clean patch of ground is convenient.

"I do not know what the makers are. Despite my mysterious yet convenient ability to speak and read your language, I have basically no knowledge of anything about this world. Because I am an alien." Probably best to make that clear right away.

This is pretty freakout worthy!! They kind of surround him and peer at him, babbling questions. Is he really an alien? How doesn't he fall over? Does his back ever hurt? Did he cut his tail off? Is he going to die because of it? Isn't he cold without fur? Several ask if they can feel his back. A tail or two brushes against him accidentally; They're very soft. 

These people are, on closer inspection, acting kinda drunk? But differently than usual. Not stumbling and slurring but definitely some kind of altered mind state going on. One of them appears to be more sober and trying to corral everyone. She has what looks like the start of a second tail, a foot long rather than the enormous nearly six foot waving fluffy mass of the first one.

In between everyone gossiping over each other about how strange this is, one of the males present explains, "About five years ago we found this old monument that, uh, pretty conclusively proves we, the species, were designed by something or someone. We call them the makers now but we know almost nothing about them."

"Except that they did a shitty job!" Another shouts over the din, to general agreement.

Yes, he's really an alien. He doesn't fall over because he has large flat feet and a portion of his brain dedicated to balance. His back does sometimes hurt, if he puts it in a poor position for too long. He has never had a tail, except for a brief period in utero, and therefore could not have cut it off. He does not expect to die of it. Sometimes he gets cold without fur, but that's what clothes are for. They can touch him if he can touch them. Avoid the genitals and eyes.

(Sid is very interested in those tails...)

"I am definitely not one of those people. I come from a planet with a bunch of people like me, no designed species. Why do you say they did a shitty job?"

This seems fine! They will feel at his back where a tail ought to be in fascination. Several people shove up tails or arms for him to touch and someone makes a joke about not minding being touched anywhere, herself.

"They put fucking poetry in our DNA instead of fixing the thing where we have bad thermoregulation and the- What's it called-"

"Metabolic cascades."

"Those."

"Or maybe they all died before they could fix us. Which is an even scarier thought."

"Guys, I'm- This is actually a really big deal, I think I'm gonna call Zand if there's no reason not to?"

"Don't! We're not supposed to be here. In the old mines, I mean."

"But an Alien is, like. A lot more important than us getting in trouble."

"You can probably feel my tailbone, at the base of my spine. That's where all the vertebrae that would have been a tail got fused together."

These people are pretty cool. Sid feels them up and pets their tails. It's great. Some of them may notice that he's getting an erection.

"Who is Zand?"

Nobody seems to think this is noteworthy. Touching and cuddly-ing continues, though a couple people are drifting away now.

"Zand is chill and has got keys to the clan's vans. He could come pick us all up. I don't want to mistreat an alien somehow. Who knows what you can teach us!"

"Can he even eat what we eat? He's probably no Vork."

"I mean, he looks like us... Do you know the word 'sucrose'? How are you speaking Unified?"

"I will let you know if I am being mistreated. I'm actually enjoying my treatment quite a bit so far."

"I do know what sucrose is, and I can eat it. I have no idea how I'm speaking your language. I certainly didn't before I got hit by a truck and ended up here."

They don't have perfect control over their tail motions. They seem to use it for balance, and they inevitably brush over places. The tips also curl up, enough to wrap around his arm, at least.

"I'm glad you like us!" Someone giggles and runs her tail over the back of his neck.

"This is too weird..."

"There's more to food than sugar..."

"Amaranth is like, the safest food, right?"

"It's a staple, that doesn't mean you can undercook it..."

"I'm not entirely sure we're not hallucinating this. And if we are, we need help. I'm getting my tablet and calling Zand."

The short-second-tail lady who declares this walks over towards the clothes pile. People hesitate but don't actually move to stop her.

"Honestly, I'm not all that worried about the food. If I don't taste or smell anything that seems inedible, I'll probably either be fine or throw it up. And if there's something in your food that will straight up kill me, I could run into that at any time, so I might as well get it over with sooner rather than later. If I die I hopefully get isekai'd again. I don't think I have the patience to meticulously verify that, like, each of the thousands of different compounds present in food is safe for me to eat."

"You should maybe be worried about disease, though. If whatever gave me your language didn't also take care of that."

"That..."

"An alarmingly good point! MIKA!"

The one going for a tablet turns around.

"Quarantine!"

Mika's eyes widen and she hisses. "Shit! Fuckdammit! Kola, lord of Plagues, you're right! We'll need to quarantine ourselves. It's the only responsible thing to do."

"Uh, how long do you guys need for the quarantine?"

"I don't know. However long it is, we'll do it."

"It'd be better for us to all kill ourselves here and now than risk a new plague."

"Sensible of you." Much more so than he'd expect from humans.

"Do we need to camp out here or is there a suitable... quarantine facility, or something, that we can live in for the duration?"

"Urgh... We need someone who isn't high to figure that out. There's the old wood house."

"This is actually important. The regional plan will give us a facility if we need it. Probably involve Doctors Without Borders."

Well, this is getting a lot more serious a lot faster than Sid thought it would five minutes ago.

"I will follow the directions of whoever isn't high. My name is Sid, by the way. Normally I introduce myself to people before I get naked with them. Or get stuck in quarantine with them. Which I suppose does give us plenty of time to get naked together."

There's a round of chuckling and then a round of names called out. Ayami, Fei, Osal, Pena, Jann, Lyra, Ka'do, and a few more.

"What are you, from Nar? Naked is the natural state of being."

"I'm least high," Mika says, "And I'm calling Zand. It'll all be okay, I'm sure."

"It occurs to me to ask what, like... What you want to happen after the quarantine. I'm sure the sixers will want to- Uh, to be very serious people at you and maybe whisk you off to a university or a military base or something, but like, that doesn't sound very fun."

Aaand he just accidentally made a joke relying on cultural context they don't have. This is trickier than he expected.

"Most members of my species—humans—have a nudity taboo. I don't, obviously."

"Being whisked off to a military base does indeed not sound very fun, although I'm not averse if the very serious people want to pay me to answer questions or give blood samples or whatever. I don't suppose any of you can get me an instrument of suicide? Ideally a gun or explosive, but I'd settle for a knife."

"Well, there's the Lilac Bridge..."

"No. It's sacred. And the Lilac Bridge might not even do anything for a- Whatever he is."

"He just said it, 'human'."

"Lilac Bridge is a suicide drug. Arguably, the suicide drug. It's kind of... Hard to explain."

"Most Kitsune* wear clothes, yes. In Luo we think they're too fussy about it. And if you were talking about sex, yes, we got that too." There's a teasing lilt in Lyra's voice.

*It literally means something liked 'tail-growing'.

"I don't feel great about the probability of success of any chemical method of suicide and would really rather have something that can rapidly physically destroy my brain, but I'll take what I can get. I don't suppose your very serious people can be trusted to do acasual bargaining or advanced decision theory or whatever?"

"I meant to reference sex as part of a humorous juxtaposition that probably mostly didn't make sense to you guys. The details aren't important."