Between 2013 and 2014, YandereDev produced several game prototypes, though none of them became popular. In March of 2014, he pitched the idea of a "schoolgirl serial killer simulator" in a forum post. The idea was met with a very positive reception, so he began working on the game.
Since the beginning of Yandere Simulator's development, he has created eight simple 'joke' games following the beginning of development: on April 16th, 2014 he released Yandere Clicker; on April Fools' 2015, he released Super Yandere 64 and Kuudere Simulator; on April Fools', 2016 he released Kuudere Simulator 2; on April 10th, 2016 he released Burning Love; on the Halloween of 2016, he released Yanderetale; on April Fools' 2017 he released Kuudere Simulator 3, and on the Halloween of 2017 he released Midori Forest.
YandereDev has also created two in-game video games: Yanvania: Senpai of the Night, which can be activated during Pippi Osu's task, and Magical Girl Pretty Miyuki. These games can be played on Ayano's gaming console in her room.
He also mentioned a "true love" project that he wanted to make. However, when he pitched it, it received a lot of negative criticism.
Inspiration to create video games: Around 15 years ago, YandereDev used to design simple video games by scribbling characters and ideas. He also tried programs such as RPG Maker but never took it seriously. He eventually became more serious about making games in 2008.
YandereDev was truly inspired to make games after playing a game called lji, which was developed by a man named Daniel Remar. The game was made by one man, so YandereDev felt like it was possible for him to do the same. It sparked his interest in learning how to program. 
Inspiration for Yandere Simulator: Before working on Yandere Simulator, YandereDev tried to develop other prototype games, but there was a lack of 3D models that he required. While searching for models, YandereDev saw a very inexpensive schoolgirl character model for sale on the Unity Asset Store. He asked a friend what type of game he would develop if he had to use that model for the protagonist. His friend suggested a "juvenile delinquent" simulator. YandereDev enjoys pushing concepts to the farthest extreme, so he wondered, "Why stop at a delinquent? Why not make her a serial killer?" From there, he pitched the idea for a "yandere simulator" to a high-traffic message board. A lot of people commented on the idea and suggested some really cool-sounding features. The hypothetical game started to sound really fun, and it seemed like people were genuinely interested in the idea, so YandereDev decided it would be worthwhile to actually develop the game.
YandereDev is known for working twelve hours a day and gave on January 8, 2016 that he has used the same scale to upload the updates since last year. YandereDev usually attempts to upload new updates on the first and fifteenth or each month. He works mainly only on the game, with the help of a few volunteers.
He initially felt insecure about his appearance and does not like the way he looks, but eventually did a face-reveal.
During his visit to Anime Expo 2016, he allowed fans to take photos with him; since then, there are now several public pictures featuring him on his blog.
His avatar is a picture of Ayano Aishi, and in his older videos, he used her to represent himself.
YandereDev is seen with black hair, brown eyes and glasses, as seen in many Anime Expo 2016 pictures. YandereDev has stated he doesn't want any pictures of him in the past because he had "nasty dark eye circles," but he eventually "came out of his shell".
YandereDev usually wakes up at 8:00 AM and starts his day with a shower. If he oversleeps, he works until 2:30 AM. On that note, he usually gets about six hours of sleep each night. While working, he usually listens to anime soundtracks, video game soundtracks, Vocaloid music, podcasts, or Let's Players commentating. YandereDev has stated that he practically has no free time.
As of December 2015, YandereDev was so burnt out from working that he changed his routine so that he only works eight hours a day, only sometimes working on the game for twelve hours. Any excess time he has now is spent live streaming games. He used to work twelve hours a day in total, with five minute breaks every hour.
In addition, he has also stated that he may not be able to update the game every two weeks anymore, due to the fact that almost all of the minor features that would only take two weeks to implement have already been implemented.
Links to YandereDev's Accounts
- Official Website
- Official Blog
- Senpai: JonTron
- Waifu: Samus Aran 
- Favorite video game character: Big Boss
- Favorite animal: Kittens
- Favorite archetype: A super lewd lady
- Favorite manga: Death Note
- Favorite anime: Neon Genesis Evangelion
- Favorite film: End of Evangelion
- Favorite bug: None. He wants to squash all code errors, but the only exception to this is the bug in Titan Mode.
- Favorite elimination method: Electrocution
- Favorite color: Black
- Favorite color scheme: Red and black
- Favorite game: The Legend of Zelda: Breath of the Wild 
- Favorite food: Pizza
- Favorite ice cream flavor: Cookies and cream
- Favorite book: Catch-22
- Favorite TV show: Breaking Bad
- YandereDev is a contributor to this Wiki and McNinja Wiki.
- The warning screen at the start of the game referred to YandereDev as "an overworked programmer".
- However, this warning was later removed because YandereDev said that it was "cringey".
- YandereDev uses Adobe Premiere to edit his videos.
- YandereDev uses Open Broadcast Software (OBS) to record his screen.
- His height is 5 feet and 11 inches the last time he measured.
- Sonic the Hedgehog was the first game YandereDev ever played, and Donkey Kong Country was the first game he ever owned.
- He admires loyalty the most in friendship.
- When asked whether he preferred Apple or Android, he explained that as a developer, making games for Android devices is easy, while making games for Apple devices is a massive pain. As a consumer, Apple devices have nice performance while Android devices are okay.
- His diet consists of food that is very easy to prepare such as bananas, PB&J, applesauce, cookies, chips, and Capri Sun if he has any.
- He has been called "Devpai" on his Twitter. YandereDev finds it humorous.
- He would really like to go to Japan someday.
- He has a very broad taste in games and will play any genre, except sports.
- His best subject in school was English.
- He learned how to program by using Game Maker. He turned it into a skill while working at an unknown company.
- If he hadn't begun work on Yandere Simulator, YandereDev states that he probably would have gone back to work at his old game company.
- He has another unfinished game which he worked on prior to Yandere Simulator.
- He has said that in the full game Ayano will get a friend request from his other game's protagonist, and through chats with her, the player can learn stuff about Ayano and the other protagonist that wouldn't be possible to learn anywhere else.
- He first started streaming video games in 2009 and wanted it to be a full-time job. Unfortunately for him, it did not work out.
- He has two cats, one named Kitty, the other named Ruby.
- If he were a Japanese schoolgirl, he believes that he would probably be a dandere.
- When a person asked about his gender, he joked that he is a 16-year-old Japanese school girl with pink hair and DD breasts. He keeps this act up when people press for more information.
- He jokes that he is actually a capybara.
- He once joked that he's a busty, pink-haired, 16-year-old, Japanese schoolgirl piloting a robotic capybara, who is piloting a robotic 28-year-old man.
- If YandereDev had his own character in Yandere Simulator, he would be in the Gaming Club, he would be a Loner, and he would have no crush.
- He has a document with all of the characters' ages, birthdays, parents' ages, etc on it.
- He never drinks coffee, as he is worried that if he uses coffee as a crutch to help him wake up or stay awake, he'll become reliant on it.
- YandereDev will say to those who pirate his game, that if they enjoy the game, they should recommend it to a friend who purchases games.
- YandereDev has relatives that play the game without realizing he is its creator.
- YandereDev mentioned in a Twitch stream, that since he has begun developing Yandere Simulator, he has gained a lot of weight, since he spends most of the day sitting in his computer chair. Mentioned at around 28:21 minutes into the stream.
- YandereDev reached 1,000,000 subscribers on YouTube, on September 17th, 2016, and 2,000,000 subscribers on April 25th, 2018.
- If YandereDev was Ayano's age, he wouldn't want to marry her, because he wouldn't want a jealous, violent, murderous, psychopathic person as a wife.
- YandereDev's favorite part of developing Yandere Simulator is hearing from the fans and seeing what they create.
- It is possible that once YandereDev is done with the game he could make his own Let's Play about it.
- YandereDev is near-sighted. He wears glasses, but he never looks beyond his PC.
- YandereDev would strongly prefer to not receive requests, suggestions, or hints.
- YandereDev does not keep old builds.
- Sailor Moon was either the first or second anime YandereDev ever watched.
- In some of the videos, he states that he sometimes wishes that he had a more simple life so he can do the things he loves since Yandere Simulator takes up most of his time during the day. Although he doesn't do his favorite things as much anymore, he still enjoys developing Yandere Simulator.
- During a stream, YandereDev mentioned that he does not enjoy pineapple on pizza.
- The three characters YandereDev enjoys planning and writing for the most are Info-chan, Ryoba Aishi, and Megami Saikou.
- In a video YandereDev said 'whoa technology' to describe a gameplay feature; this phrase later garnered attention and became an internet meme.
- He was interviewed by Bijuu Mike in 2017.
- He has a wiki account, but he tells people not to message him on it because it sends him too many annoying emails.
|“||Read the FAQ.||”|
— When someone asks him a question that is in the FAQ.
|“||Thank you for following the development of Yandere Simulator.||”|
— YandereDev thanking the audience for watching his progress at the end of nearly all of his videos and blog posts.