In 2077, "cognitive pollution" incidents occurred frequently around the world - ordinary people suddenly claimed to see "moving black shadows" and "scarlet pupils", or heard inhuman whispers, and then fell into madness, self-mutilation or even disappeared. Officials define such people as "patients with super-sensory paranoia" and are imprisoned in seven "special sanatoriums" around the world. They claim to be "mental illness treatment institutions", but in fact they are mankind's last line of defense against the invasion of the "Shadow Realm".
