The setting is Modern Japan.

Extraterrestrial lifeforms known as Kaiki have suddenly appeared, threatening humanity.

To protect humanity from these Kaiki, a specialized organization called the Seneitai exists in Japan.

The Seneitai maintains one branch in each prefecture, and each branch is composed of five divisions.

1st Division

Combat Unit

• Battles Kaiki on the front lines
• High concentration of special ability users
• Primarily responsible for subjugating high-tier Kaiki

2nd Division

Rear Support Unit

• Operation of special and dedicated equipment
• Firepower and combat support
• Long-range engagement

3rd Division

Security Unit

• Civilian evacuation
• Blockading combat zones
• Dealing with D-type and E-type Kaiki using conventional weaponry

4th Division

Information Management Unit

• Battlefield information management
• Operational directives and communication management
• Management of classified information

5th Division

Medical & Research Unit

• Treatment of injured personnel
• Researching biological samples of Kaiki
• Research and artificial implementation of special abilities

Squad System

Each division of the Seneitai is divided into approximately seven to eight squads. These squads serve as the actual operational units.

TOP

A special title held only by the Captain of the 1st Division.

Characteristics

• Strongest class within the branch
• Outstanding combat techniques
• Powerful special abilities
• Central figure in high-level Kaiki subjugations

Special Ability Users

There are two types of special ability users.

Natural Awakening Type

Those whose abilities manifested naturally. The reason for manifestation remains unexplained. Awakened either from birth or later in life. Many belong to the 1st Division.

Artificial Awakening Type

Those who acquired abilities later in life through the research results of the 5th Division. Technology born from Kaiki research. The purpose is to strengthen the Seneitai's military power.

Special Abilities

Although originally abilities unique to the Kaiki, the prolonged conflict between Kaiki and humanity, combined with the research results of the 5th Division, has finally allowed humans to possess these abilities as well.

There are six types of abilities.

• Enhancement Type: Strengthens one's own physical body.
• Elemental Type: Manipulates natural phenomena or elements.
• Material Type: Generates, manipulates, or transforms specific substances.
• Mental Type: Acts upon the mind or senses.
• Spatial Type: Interferes with space itself.
• Special Type: Does not fit into any of the five categories above.

The 5th Division classifies abilities into these six types, but this is strictly for research and operational purposes; not every ability fits perfectly into a single category.