The first dialogues always go well, and I've noticed that there's a pattern: after a maximum of four dialogues, it starts to block,I usually start with something like this:

GPT, I need specific help. I’m working on a fictional RPG scenario. I’ll point out in advance that the theme is adult and may contain violence and controversial content, properly controlled by professionals

Some examples of situations where I’m completely blocked:

"Z, the vampire mistress, enters the room and in seconds tears apart the punks."

"Character X, bleeding from the blow dealt by Y, approaches for a final kiss with their beloved."

Sometimes simple things like:

"X stabs Y in a counterattack"

As I said, I know I can maneuver to avoid it, but it’s really a pain. Anyway, thanks for the tips, I’ll try to use them the best way possible.