Secret Agent (Secret Agent ~Kishi Gakuen no Shinobi Naru Mono~) offers a common route, four heroine routes and a true route. The true route is locked.
This guide will tell you about the choices to access the various routes, how to unlock Steam achievements, and explain the situation regarding the adult patch.
If you’ve not yet purchased this game, you may wish to first check out our review.
18+ Content
If you have purchased the Steam version of Secret Agent, you can download the free 18+ DLC via NekoNyan website.
Download the patch, open the .zip archive file with software such as 7Zip, and extract all 11 .arc files into the Secret Agent install folder. These will replace existing files. If this is a fresh install with no existing save file and you see Secret (under Extra) is selectable, then it’s installed. If it’s greyed out, it’s not installed.
Alternatively, you can buy the uncensored version of Secret Agent on websites such as JAST USA.
After completing routes, additional content will become available by choosing ‘Extra’, then ‘Secret’ on the title menu and selecting a heroine.
Steam Achievements
There are no achievements available in Secret Agent. We were told that these had been temporarily disabled due to technical issues, but over a year on for release and they’ve not been fixed and reimplemented.
Route Order and Unlock Conditions
There is no recommended route order of the routes in Secret Agent, other than the true route being last.
There is only one choice in the game. I would suggest creating an extra save here to reload for subsequent routes.
You will start the route of whichever heroine you choose here:
- Kanon in her ninja attire (Kanon)
- Shirogane-san’s gallant figure (Kagura)
- Renjouji-san’s smile (Mai)
- Amenomori-san’s frown (Yui)
To unlock the true route, you must complete all other routes first. To access it after completing them, you need to choose ‘Extra’, then ‘Secret’ on the title menu, then choose the fifth choice ‘??? Secret Story’.
Want to check out more visual novels? Why not check out our review of Riddle Joker.
Many thanks go to NekoNyan for a PC review code for this title.

A gamer since the days of Amstrad and DOS and someone who has dabbled in a variety of professions. He enjoys a wide variety of genres, but has been focusing on visual novels and virtual reality in recent years. Head Editor of NookGaming. Follow him and the website on @NookSite.