Developer: Lunarian
Publisher: Lunarian
Release date:
Version: Demo
Language: Japanese (Official)
Censored: Yes (Mosaics)

The perverted religion's pleasure brainwashing erodes everyday life! Can the skilled agent save the academy stained by the chain of evil's fall!?
This game is an exploration-based AVG.

It is the sequel to the previous title, “Agent Sirius: Even a Girl Vulnerable to Pleasure Wants to Protect Her School from Brainwashing Monsters!”,
and the previous DLC, “Agent Sirius DLC/NTR: Kingdom of Betrayal”.

The game progresses in the format: Prologue → Exploration → Next Chapter.
There is also a “Dark Side Route” where you can fully indulge in the chain of corruption.


Enjoy a story where you can slowly savor the perverted cult's gradual takeover of the academy!!


Collection elements have been significantly enhanced compared to the previous title!
Gather scattered
“Help Points” throughout the school to unlock “Sub-Events (Erotic Scenes)”, the “Monster Encyclopedia”, and the “World Guide”.
You can also check character changes in the “Fallen Encyclopedia”.