[Several thousand years in the future]
Humanity had spread to 100 solar systems. We had also discovered several anomalies in spacetime where it would seem your ship was randomly transported to another spot.
As an escaping criminal, I was headed for one of those. (My crime? I had taken the local Governor of the system out of a business double. We made three no trump and won the rubber, but it didn't matter to the Governor. He ordered me sentenced to life imprisonment.) I had knocked two guards unconscious, stolen the spaceship and blasted out of the system before they could realize I was gone. I had three hundred police ships chasing me, but if I reached the anomaly, I knew they wouldn't pursue. If they went through they wouldn't be near me anyway - random transport means random. I had the thrusters on max. Five... four... three... two... one...
And that was that! Now to find a place to land this thing. I didn't have a whole lot of fuel left. I killed the thrusters and scanned the area. One planet looked habitable. I aimed for it. A quick atmospheric sample revealed the air was breathable. The planet didn't have much in the way of vegetation or water. I could only see a single body of water in the area, though it was large, about 500 miles or so in diameter. I came to a rough landing, more like a crash, about 50 meters from the lake. The ship wouldn't fly again, so I salvaged the rations and then set it on fire, just in case the police ships somehow found this place. They would assume I had died in the charred remains of the ship.
I walked over to the lake and filled my large jug with water, then found a small stand of vegetation on the lake's edge and constructed a simple lean-to. I hadn't seen any signs of life, but I figured there had to be some living creatures. Tired from my exertions, I made some leaves and grasses into a bed that would be softer than the dirt and rock, and I slept.
When I woke, the first thing that struck me was the heat. Literally. A pulse of hot air smashed into me. I shook myself awake and looked over towards the heat source.
A female humanoid was standing near me. She seemed to be where the heat was radiating from, and the parts of her skin I could see looked almost like magma.
"Hello," she said.
"Um, hi? How do you speak my language?"
"I mastered it from reading your mind while you slept. I am Lava Teen, though the name is outdated. I am 25 of your years old, which makes me three years younger than you."
"Nice to meet you, I guess. I'm Ben. Where am I?"
"This is Lake Solo. It is the only body of water on the planet. My species does not need water. Our capital city is about ten miles that way."
She pointed to indicate a direction.
"I came over to investigate the fire. We like fire, you see. I consumed some of the molten metal. Molten metal is a delicacy. We normally have to heat rocks."
I wondered how Lake Solo still existed.
"This is the coolest spot on the planet, and when we get rain, it is always directly over the center of the lake."
Lava Teen seemed to adjust something about her body, and she was no longer radiating heat. She extended her hand down and helped me to my feet. Her skin was noticeably warm, but not burning hot.
"Shall I take you to my quarters in the city?"
"You may not need water, but I do."
"Do not worry. I have water in my quarters. I do sometimes like to touch it. The feel of it on my skin is interesting. So I arranged for a piping system to run the water from Lake Solo. A few other of us also have a similar system, though most do not."
Lava Teen took my hand and started to lead me out of the lean-to. I broke away to gather my rations.
"Is that what you eat?"
"Yes..."
I realized there was only enough for 100 or so days. What would I do afterwards?
"Our chemists can analyze one of those and then synthesize something that will provide you with nutrition."
"Thanks."
Lava Teen installed me in her quarters. Since she had found me, I was now her possession, according to her society's rules. The substance her chemists synthesized seemed to be keeping me in perfect health, and there was sufficient water provided to me that I stayed hydrated. It had been six months since the crash before I knew it.
Lava Teen didn't know how her species had evolved, but there were a few thousand of them on the planet, most of whom lived in the capital city. They were made of molten stone and metal, solid on the outside, and did not need to breathe. They just needed to consume enough stone or metal to replace the amount lost by wear and tear. And they didn't talk very much to each other: the social preference was to live alone. They did not reproduce, but a new one could be created by melting stone and metal and then shaping it and letting it solidify. How the consciousness arose during this part, she didn't know: at age 25, she was by far the youngest in existence. Most of the others were tens of thousands of years old.
"So much for me. What about you, Ben?"
"My species is made of flesh, needs to consume food and water daily, and reproduces by... well, let's just say we aren't constructed. A male must inject his genetic material into a special location within the female to produce a new human. As for myself..."
I explained why I had fled from my own species and crashed on this planet.
"That is a strange way to produce a new member of your species. What part of you does the injecting?"
I suppose I should have known she'd be curious about that. I removed my clothes and stroked my cock to its full hardness.
"This part. A human female has an opening between her legs." I pointed at the solid rock making up Lava Teen's crotch. "The male injects the material there, and if everything goes well, it mingles with the female's genetic material. Then the combination grows for about nine months within the female's body, at which point she expels it through the opening. We call the process birth and the newly born human a baby. The baby takes about 18 to 20 years to fully mature into an adult human. During that time, one or both of the male and female who united to produce it make sure the baby has the resources needed to properly grow and prepare for integrating into adult human society."
"How very inefficient," she mused. "I much prefer our method, where the newly created one of us is immediately ready to take their place without waiting 18 to 20 years." She stared at my cock. "What is the substance you inject to produce a baby?"
