Due to a meteorite 400 years ago, monsters that must devour human flesh and blood to survive were born into the world. They excel at hiding among crowds and stalking their prey—they are called variants. In response, the Federation established the Federal Variant Countermeasures Bureau, also known as “FACA,” which uses variant genetic cells to cultivate excellent Executors to combat the variants. An Ran is one of the most outstanding Executors, but he harbors a secret deep in his heart—another identity, as the variant “she”…