Agent Sirius is an adult exploration and puzzle-based RPG developed by Lunarian. The game follows Suzaku Akane, the head of a detective club who also serves as a secret society agent investigating mysterious events at her academy. Core Game Overview (RJ388166)
The base game, identified by the DLsite product code RJ388166, is primarily an investigation-style adventure.
Protagonist: Suzaku Akane, an agent working with her partner and overseer, Byakko Nadeshiko.
Plot: Akane must identify a villain who is using "pleasure brainwashing" to dominate students before the academy falls completely.
Gameplay: The loop involves exploring the school, talking to eight different suspects, and piecing together clues in a specific order. Players who get stuck can find a guide in the nurse’s office for hints. DLC Expansion: "Kingdom of Betrayal" (RJ01259073)
The DLC, identified as RJ01259073, is titled "Uragiri no Kingdom" (Kingdom of Betrayal). eng agent sirius dlc rj388166 rj01259073 verified
The Story: This expansion shifts the focus toward a "darker" route involving a character named Akezubeni and a conflict against an intellectual charlatan, Noroshi Ren.
New Content: It features what is described as an "NTR chain fall" narrative, significantly expanding on the base game’s themes of corruption and moral fall.
Availability: Verified English translations for both the base game and this DLC are available on platforms like RyuuGames and Lewd.ninja. Key Features of the Verified English Version
The "verified" English release typically includes the base game updated to Version 1.01 along with the integrated DLC.
Enhanced Collection: The collection elements and gallery features are significantly strengthened compared to the original release. Agent Sirius is an adult exploration and puzzle-based
Multi-Route Narrative: Includes the "Dark Side Route" where players can explore the full extent of the school's corruption by a perverted religion.
Community Patches: Discussions and requests for these translations often originate on forums like F95zone, where "verified" status often refers to a working, stable English-translated build.
The phrase "eng agent verified" is unofficial terminology. It does not appear in DLsite’s official metadata. Instead, it originates from:
Thus, the full keyword describes: "An English translation DLC for the game Sirius (RJ388166), produced by an agent/group, and verified as stable and complete, with the supplementary ID RJ01259073 acting as the patch or proof of verification."
For those verifying the IDs:
I played the "Complete" version incorporating this DLC. I am happy to report that optimization is excellent. The loading screens are snappy, and I experienced zero frame drops even during the most chaotic scenes with multiple enemies on screen. The UI updates are clean, making it easier to track the new status ailments introduced in the DLC.
If you searched for this keyword, you likely want to play Sirius in English. Here is the step-by-step process as of 2025:
Even with a verified DLC, problems can arise:
Issue: Game crashes after patch install.
Solution: Run verify.exe again. If it shows "Patch mismatch", re-download RJ01259073 from the agent’s official source. Corrupted downloads are common.
Issue: Text is cut off or overlapping.
Solution: The default font lacks kerning. Download the agent’s recommended font pack (FreeMono or Noto Sans CJK) and place custom_font.ttf in the game’s root directory. Thus, the full keyword describes: "An English translation
Issue: "Agent Sirius DLC not recognized" error.
Solution: This means you installed the patch over the wrong game version. Update RJ388166 to v1.08 or higher via DLsite’s update section. Then reapply the agent DLC.
Issue: Save file says "Japanese only" after English patch.
Solution: Verified patch v2.1 and above supports cross-language saves. But you must start a new game for the first run. Old Japanese saves will show garbled text.