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Hey /adv/, I'm currently writing a script for a Katawa Shoujo mod and could use some writing advice.
The Concept:
It’s a 4-act mystery and psychological thriller. I want to step away from the usual slice-of-life romance and focus heavily on themes of anxiety, paranoia, and psychological horror.
The Plot:
The stress and his heavy heart medication trigger severe anxiety in Hisao. While trying to cope, he starts finding strange notes and noticing unsettling, out-of-context remarks from the girls and other characters. This drives him into deep paranoia, making him distrust everyone. The big twist is that Kenji is actually stalking him, but I need to keep this a complete secret until the very end.
The Problem:
How can I effectively write this slow build-up of anxiety and paranoia? What kind of subtle, weird details (besides the notes) can I add to make the atmosphere progressively more unsettling?
I really want to know how to write a compelling mystery that keeps the reader hooked without the pacing dragging. Any tips on writing genuine psychological horror for a VN or pacing the tension across the acts are appreciated.