An oblivious adventurer comes across some hot springs. They gratefully shed all their equipment in one go and dive in. The water's heavenly.
When the heat has relaxed them completely, they're too sleepy to notice any movement in the water. By the first touch it's already too late. They can only hang on as something smooth and girthy slips inside.
It's in so deep, so quickly. And it's undulating, setting a ruthless pace and making the adventurer throw their head back and scream in utter terror melting to confused pleasure. It's almost like they're melting, dissolving into the water, until they don't know where their body begins and ends.
The first egg, fist-sized and soft-skinned, squeezes inside unnoticed. Quickly followed by another. And another.
Half a dozen sit in the adventurer's womb by the time they notice anything. A twinge has them looking down at their formerly flat stomach. It's round now, a little swell sitting ominously low.
But their eyes skip further down, to the weirdly formless being between their legs. It's hard to see, translucent, invisible but for its frenetic movement.
If the water were calm and the watcher alert and keen-eyed, they might be able to spot an overstuffed egg sac emptying swiftly.
They might have predicted the adventurer's fate before the creature's subtle venom made them lethargic and pliant.
As it is, they don't have to the presence of mind to even contemplate escape. Which is why the creature has pulled this exact same trick many times before.
And it's succeeded again.
By the time the adventurer's mind starts to clear, it will have already made its way deep, deep into the spring.
They come to in placid water, only disturbed by the minute movements of--or rather, in--their swollen stomach.
The little twinges and twitches draw the adventurer's attention, but their current predicament still fails to register.
Their gaze and fingertips explore the ample surface without conscious thought.
Dazed, they rise out of the water on shaky legs. Unexpected heaviness pulls them down.
They scramble on the rocks to stay upright. Unfamiliar weight hangs under them. They look down.
A stranger's body. That's their first instinct. It's unbelievable that the blatantly gravid belly is theirs.
Stumbling onto dry land and clumsily pulling on their clothes breaks the spell. The tunic won't go down. The trousers won't go up.
And between them sits an egg-stuffed womb that undulates gently, like water around a swimmer's skin.
The way back to town takes thrice as long as their entire trip so far.
By the time they collapse on the healer's doorstep, the first egg is already crowning.
Miles away, in a desolate landscape, two tired mercenaries stumble upon a hotspring. While saying a little prayer of thanks, their armour is already hitting the ground. They get in without a second thought.
