Evolution's a complicated process. There aren't rules or paths or obvious solutions to obstacles. Just a goal, and one that keeps moving. The goal itself is, in fact, Keep Moving. Your species survives by being faster, by being stronger or smarter, or at the very least by not tasting very good. Or by being so cute that some other well-off species takes you under its wing and out of the race entirely, which is certainly one way to win it.
The result was this: a world - no, that word gave the wrong impression. Worlds were more...abstract, in a way. All-encompassing by nature. This was just a planet. A planet where a species very similar to homo sapiens had been found either useful or aesthetically pleasing by another life form deep in the planet's past, and these days were mostly considered luxury pets. Almost every human here was bred for beauty and affection. Still a fine form of weapon in the evolutionary arms race.
Thoughts of that nature slowly spun around themselves in Trace's head while he ambled his way up what appeared to be a monolithic garbage bin. Thinking about this world he'd landed on from the standpoint of pure scientific inquiry helped him feel like he was doing more than acting like a stray alley cat, slipping into unguarded homes and getting to know the...locals.
And he'd found a good one here. She was pudgy and adorable, carrying her weight in a fine pair shape. A plump ass and fluffy stomach and simply fantastic tits; ginger hair that spilled around her head in curly waves while she laid on her back. The woman - younger than he was, not by much - didn't seem occupied by anything, eyes staring at nothing towards the ceiling, feet occasionally moving to the rhythm of music playing ambiently in the house. Sprawled out on a bed the size of Trace's entire quarters back on his modest little ship.
The feeling of something else crawling along the bed caught her attention from her daydreaming, and a shimmer of light made her look directly at him. "Stranger?" Her voice was quiet and sweet. Not really concerned; obviously she was safe in her own home. Only curious. She didn't see many other people. Strictly an indoor human, looked like.
She wasn't wearing much. Indoor humans, Trace had noticed, tended not to. A collar to indicate ownership, with a cloak hanging from it that she could wrap up in if it got chilly. The effect was dramatic, a black cape against pale skin and red hair. "Stranger." Trace repeated the word for her, simply acknowledging himself for her. It wasn't a question of threat she'd posed; she just needed to be reminded if she'd seen him before or not.
Comparatively, he was wearing a lot of clothing. Durable pants, a long-sleeved coat, a couple layers of shirt and thermal underwear. The best guess anyone on this planet who had spotted him could make was that he was a VERY outdoor human. They weren't wrong. He was about as outdoorsy as you could get, if you consider space flight and planet hopping the out of doors. Didn't take much effort to get out of the parts of his clothing that mattered though, because space farers still had to pee (most of them, at least). Unceremoniously, he retrieved his cock - stiff and ready, fat and hungry, and held it in the base of his palm for her to appraise.
She looked curious at first, still blinking back the daze of vegetation, before she offered him a positive nod and a gentle smile. "Love you!" The humans here only knew so many phrases, and this one was pretty versatile. Their owners loved to hear it, so they said it after meals, after baths, after being given toys, and as he'd noticed first hand, before being given the chance to breed. She rolled onto her knees, thighs spread wide, and placed her hands on the backs of her legs - intending to spread her pussy lips for him, but mostly just straining the cloth of her cloak.
The other thing about the humans on this planet is they weren't always very bright. Trace did the job of pushing her cape out of the way for her, which got another quiet 'love you' out of her. Her pussy was perfect and pink on the inside, beginning to drip with lust and need almost instantly at the prospect of being put to use. His teeth bit into the leather of his gloves and pulled them off so he could touch her directly, rough skin of his fingers against her flawless body, sliding adoringly up her legs and squeezing gently to appreciate the plush feel under his fingertips. Her figure was incredible, her face matching it to make her look perfect for the role of cuddly and affectionate housepet - though he doubted her owners had an appreciation for how fuckable her form was.
His tongue earned a surprised cry from her as he began lapping at that presented slit, a hand pressing into her supple ass cheek and pressing a thumb up against her tight asshole, slooowly working its way into her, holding her steady while he enjoyed his snack; kissing and loudly smacking and humming against her velvet lips, thumb on his other hand coming up to locate her clit and rub circles around the surface of it. His nameless friend writhed and squaked uselessly against him, not really sure what to make of this happening, but probably enjoying it. Her fingers gripped at the blanket beneath her, thicker than her hands, while rocking forward and back against him purely on instinct.