With a swing of your sword, you inflict a mortal wound on the girl, and she falls to the ground. She doesn't scream... she doesn't seem to have any pain.

Drowning in blood, her eyes come back to normal for a second and says, "Run, he's coming."

Frightened, you turn and run, but you feel a searing pain inside your head, freezing you in place. A mindflayer steps into view, its grotesque, tentacled face twisting into something resembling a smile, floating using its mind powers.

Its psychic grip tightens, rendering you unable to move or think clearly. You feel his slimy tentacles brush against your face and head, his touch cold and invasive. Slowly, your resistance fades, replaced by a strange calm. You start to relax and hear his voice inside your head. "You killed my servant, and I need a woman for my experiments. I will make some modifications to your body."

After that, everything is dark, and you have weird dreams with magic cristals and you have a numb sensation between your legs.

You wake up tied up in a strange stretcher.
The creature looks at you with his tentacles wriggling on his face. Inside your head, you listen...
"You are finally awake... I need you to be awake and lucid, pain is an important part of this procedure."
He takes a worm-like parasite with his fingers and continues.
"With your pussy I will produce an army of lesser mind flayers who will obey me. I just need more adjustments."

Wait, what he's saying??? Your pussy?? horrified and humiliated, you watch something incredible... your penis and testicles are gone, and you have a well-lubed vagina.
You try to resist, but he says that you are warmed up and the process starts.

You feel the parasite inside your urethra, the pain is impossible to endure, but when you think that this can't be worse, the mind flayer takes a metal speculum and inserts it in your pussy to spread it open and expose your cervix... then he starts to insert a parasite directly inside it.

With no more strength left, you beg him to stop, but he doesn't have any more patience. He takes off the speculum, grabs a bunch of parasites, and he inserts his whole fist inside you.
You scream in pain, begging him to stop, but he doesn't care about your human emotions and wellness.

Unfortunately, your modified body can't endure the parasites, and you feel weak, very weak...
After a few minutes, the pain stops, your eyes close, and this is...

THE END

Bad Ending
Mindflayer's Brutal Experiment

Task: On a table, put 2 chairs to rest your feet and simulate a gynecological chair. Poke your urethra using a small dildo and imagine the parasite inside you, act frightened, and moan in pain.
Insert a speculum in your ass (or pussy if you are female) and poke as deep as possible with a long, small dildo or a rounded metal spoon. Struggle, continue to moan, and imagine the terrible experiment.
Take off the speculum and use a huge dildo to impale your ass or pussy, scream and struggle in pain, and then act weak... pretend to fall asleep.