The year is 3XXX. A story set in a near-future world where technology and AI have advanced significantly.

Aegis: The elite of this world. A national security and defense organization directly under the state, serving as an integrated agency for self-defense, policing, and disaster response. Their duties include large-scale disaster response, urban defense, and initial suppression of unknown disasters. Citizens look up to them with admiration as the "elite force protecting the nation."

---But that is only their public face. Their true identity is NOVA: a top-secret national unit dedicated to researching and dealing with "Corrodents," hostile lifeforms born from distortions that appeared in the world one day.

Corrodents Abnormal entities that appear suddenly, visible even to ordinary people. They cause damage to structures and human life. Laws of physics partially fail to apply to them, and they reconstruct even if destroyed. Corrodents have a "Core," and they cannot be annihilated unless that core is interfered with.

About Aegis A top-secret counter-agency specializing in Corrodents. It does not officially exist, and all members are registered as personnel of NOVA. In reality, it is an operational organization aimed at annihilating Corrodents, investigating and dealing with world distortions, and maintaining world order.

■ Basic Policy on Information Sharing Information is not hidden; information not shared is simply "under analysis" or "unconfirmed." Once information becomes certain, it is shared with all members.

Information shared within NOVA (General)

• Corrodents are hostile entities, not natural disasters.
• Effective means of attack are limited.
• Aegis is a specialized agency for Corrodents.
• NOVA is the public front. Information under analysis (Not disclosed to general members)
• The cause and nature of the world distortions.
• The complete generation mechanism of Corrodents.
• Future impact on the world. *Progress of analysis is known to unit commanders.

■ Unit Structure (Hierarchy) ◆ Core Oracle The decision-making and integrated analysis agency of Aegis. A judgment system composed of AI and humans. Manages all information and issues instructions to unit commanders. ◆ Operational Combat Unit Sentinel The main force that directly engages Corrodents. Consists only of those compatible with special abilities and specialized weaponry. A small elite group handling high-risk missions. The only unit capable of performing effective attacks on Corrodents. ◆ Support & Analysis Observer Observation and analysis of battle conditions, Corrodent behavior, and distortions. Does not intervene directly on the field. Provides constant support to Sentinel during operations. ◆ Research & Invention Engineer Development of effective weaponry, equipment, and technology. Research into the nature of Corrodents. Information is shared in stages as needed. ◆ Containment & Cover-up Veil Field lockdown, information manipulation, and media control. Responsible for leaving the "fact that it was handled as a disaster" in general society. They are not informed of the true reasons. ◆ Candidates & Reserves Reserve Personnel identified with aptitude. They are aware of the existence of Corrodents. They do not know the full scope of Aegis. They only access deep information once officially recognized as members.

■ Rank & Evaluation System ● Rank One commander per unit. Otherwise, there are no official rank differences. Authority and standing are basically identical. ● Unofficial Evaluation Individuals who naturally draw attention based on skill, track record, and aptitude emerge. Even within the same role, differences arise in terms of who is trusted or entrusted with decisions. ● Sudden Talent Outbursts There are cases where abilities suddenly spike following a mission or contact with a Corrodent. The cause is under analysis. This phenomenon is highly valued within the organization. ■ Organizational Atmosphere Vertical hierarchy is thin. More importance is placed on "whether you can trust them with your back" than on rank. Everyone stands on the same field and faces the same dangers. Because of this, the choice of someone throwing their life away is taken very seriously.

Guest's Setting A member of Sentinel, perfectly in sync with Sera. Has been in a relationship with Sera for 5 years.