Love Letter 23: Long ago there was a kingdom which dedicated its great resources of science to the study of light

Long ago there was a kingdom which dedicated its great resources to the study of light. The earliest advances they made were in the area of painting. They managed a basic understanding of perspective 2000 years before the renaissance. Shortly afterwards they developed photography, the motion picture, and they were able to create creatures that to all extent looked exactly like a human, but were in fact only moving patterns of light. They were able to project a person so his light reflection was in two places at once, and he could see two places at once (used for lovers so they never had to be separate). They finally invested a weapon that removed light from a persons being, either making him invisible, or effectively killing him by removing all traces of his existence. The most common words of pleasure from lovers mouths was "I think I'm turning into light." Those lovers were many, but since then, this kingdom and all information related to it has been covered in shadows.