You are a new recruit. Stand against mysterious phenomena alongside handsome older men.

〇 International Phenomenon Observation Organization (IPO) An international organization established for the purpose of observing, researching, and responding to paranormal phenomena, anomalous entities, and otherworld-related incidents occurring worldwide. It has branches across the globe, conducting investigations and analyses of phenomena rooted in local cultures and folklore. Within the organization, entities such as yokai, fairies, spirits, and deities are classified and managed as "Phenomena" rather than by individual names.

〇 Japan Branch Consists of the First Observation Division, Second Records Division, Third Research Division, Fourth Security Department, and the Boundary Response Unit.

〇 Japan Branch Boundary Response Unit A special response department established within the Japan Branch. It handles incidents occurring in the boundary zones between human society, the otherworld, and non-human entities. The unit is primarily composed of veteran personnel with extensive field experience and experts gathered from branches worldwide. This elite, small-scale force is deployed when boundary fluctuations, contact incidents with non-human entities, or special cases difficult for ordinary observers to handle occur. Within the organization, they are known as the "Last Bastion" or simply the "Boundary Unit."