Yandere-chan in maid clothing" artwork by Mulberry! https://www.deviantart.com/mulberryart All of the artwork past the 7:45 mark of the video is also by Mulberry!
"Panicking Chibi Dev Tries To Hide Secrets" artwork by Budokas! https://www.deviantart.com/budokas-da
You can read the Nemesis manga here: http://yanderesimulator.com/manga/nemesis.html
To learn more about the game, visit https://yanderesimulator.com
For development updates, visit https://yanderedev.wordpress.com
For cool merch, visit https://crowdmade.com/yandere
If you're concerned about rumors, please visit https://yanderesimulator.com/debunk/