What if you make a game where you walk in a crowd of NPCs and a few of them pull up a pistol or shiv if you get too close?
Aesthetic could be very noir and shadowy with the player being a pure white or red color, making them stand out and easier to locate
Would probably work well to have a few levels all with a new crowd layout, so it might be a remembering game or similar
Not using the idea so you can have it if you want