Saikou Corp is a business conglomerate whose logo appears on various devices in Yandere Simulator.
The company has appeared many times throughout the debug builds, even as early as the October 8th, 2015 Build where the school's logo was shown on a social media page. The symbol at the center of the logo was "Saikou (最高)" which means "The Best". With arrows pointing in all directions, it means "The best at everything". YandereDev has also stated that Yandere-chan's computer runs on SaikouOS. Her console is the SaikouStation4.
After playing the final level of Yanvania: Senpai of the Night, the game will crash because the disc is scratched. There will be a console error on the screen that tells the player to visit 'www.saikoucorp.com/support' for more help. This is not a real website.
The logo later appeared in the December 15th, 2015 Build on the back of the laptop inside the Student Council Room, used by Megami Saikou to talk to Yandere-chan. In the February 1st, 2016 Build, the brand was shown on the camera worn by Yandere-chan if the player joins the Photography Club.
As of the April 3rd, 2016 Build, Yandere-chan now uses a black Saikou phone.
As of the May 1st, 2016 Build, Genka Kunahito uses a Saikou computer.
As of the June 29th, 2016 Build, several Saikou devices can be found in the Faculty Room, such as a clock, a radio, a printer, and a computer. The radio was moved inside the Audiovisual Room and made functional.
As of the December 16th, 2016 Build, several Saikou metal detectors will appear in the school corridors, if enabled in Mission Mode.
As of the May 19th, 2017 Build, there is a cardboard box with the Saikou logo on it inside the northeastern storage room, on the first floor.
- There may be a real Saikou Corp website that YandereDev will create himself in the future.
- The button on the Saikou phone can also be found on the male uniform.
- Pippi Osu owns a SaikouStation 4.
- Kocho Shuyona will refer to a "Mr. Saikou" during some Game Over screens.