Hello, Google Translate! If I understand you correctly, this should be relevant to your problems. I will try to explain this in the most translator-friendly way possible.
I will first say that none of the things you have mentioned are relevant to difficulty level as far as I understand. Difficulty level primarily determines the frequency of events which permanently lower the player character's stats. So at higher difficulties your character is increasingly likely to become weaker as the game progresses instead of stronger.
Different NPC's have different requirements to cause aggression, but a common determining factor is how lewd your clothing is. The more lewd your attire is, the more chance for aggression. The NPC must also notice the player character. Sometimes simply stepping on the same tile does not alert the NPC of your presence, many factors are at play in that regard.
Another point to mention is that occasionally staying still for several turns is intentional behavior in the NPC's. If they moved more frequently, it would be easier to avoid them by waiting until they leave the tile you wish to access. By staying in the same place for a long time, the player must make the choice to either avoid that tile entirely or risk the NPC aggression. This is an even greater dilemma if there are many hostile NPC's sharing the same tile because being outnumbered poses a greater risk even if they are relatively weak enemies alone.
Due to performance reasons, there is a limit to how many NPC's may be present on a floor at once as the game engine must calculate the next move for every NPC with every passing turn. When this limit has not yet been reached or an enemy has been banished, the way new NPC's are added to a floor over time is determined by a surprisingly complex system and depends which floor you are on. As a general rule, more orgasms received or turns spent masturbating will reduce the time it takes for the next NPC to spawn. However there is no guarantee this NPC will be instantly hostile to the player.
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I hope this has been helpful.