Blood and Incinerators


I’ve been working on blood-related stuff lately. Here’s what’s new:

  • When you stab a victim, blood sprays out of the wound.
  • A dead body creates a pool of blood.
  • Dragging a dead body creates a trail of blood.
  • Stepping in a pool of blood causes you to leave bloody footprints with each step.
  • You can make drawings using a girl’s blood.

Here’s a WEBM of the new blood features in action:

Also, I’ve added a way to dispose of dead bodies; incinerators. Drag a corpse over to an incinerator, toss it in, activate the incinerator, and you’ll have one less problem.

Here’s a WEBM of an incinerator in action:

Webm Gallery

Here’s a gallery of video clips that I’ve made while working on the game, in webm format. Please note that all of the below animations are temporary placeholders.

Funny bug that happened while giving NPCs the ability to watch Yandere-chan:

Demonstration of real-time mesh deformation and preview of potential character customization:

Building a staircase out of dead bodies to reach previously inaccessible areas:

Visual Novel Preview:

Visual Novel Preview with tiny heads and huge hands:

Visual Novel Preview with chainsaws for hands:

Visual Novel Preview

It’s been two weeks since my last update, so I thought I’d post something up here to let you guys know that the game is still happening.

Today, I wrote a script that makes it easy to define what facial expression / animation a character should be displaying during the “visual novel” segments. It’s pretty easy to create entire dialogue sequences now, complete with the characters’ models moving around and emoting appropriately.

Please keep in mind that the character models aren’t final, the animations aren’t final, the dialogue isn’t final, the background art isn’t final, etc – I just wanted to confirm that I’m still developing the game.

Audio Design and Music Demos

EDIT: This blog post once had links to vocaroo tracks, but it looks like those links have expired, so you can no longer listen to the test tracks that were made for this game.

It’s been two weeks since the last update, so I’d like to post something cool to let you know that this project is still alive.

I was fortunate enough to be contacted by a very talented musician who has produced some tracks that closely match my ideas for the game’s soundtrack. The idea is that we only hear one melody during gameplay, but depending on the player’s actions, that melody is altered to sound soothing, unsettling, or outright horrifying. Here are some music samples that, hopefully, convey what I’m talking about:

Peaceful Music: Broken link

Doing-Something-Suspicious Music: Broken link (The same track as above, but edited to sound more creepy)

In addition to using one melody that sounds progressively more disturbing depending on the player’s actions, we might completely change to a new track once the player has been spotted, or has limited time to perform an urgent task.

Endangered Music: Broken link (Too dramatic? Better suited for a battle in a Final Fantasy game?)

Here’s another track that I feel would be right at home during an especially creepy moment; when Yandere-chan opens an envelope that says “I know what you did”, or when Yandere-chan or has a subtley threatening conversation with a girl, or when she arranges pictures of Senpai-kun in her room. It might also be appropriate gameplay background music for certain situations, such as trespassing in the school after midnight.

Creepy Music: Broken link

The last track I’d like to share with you is a “concept” track created by another musician. It’s not a track that would actually appear in the game, this track is only meant to demonstrates how the tone of the music might change throughout gameplay depending on the player’s actions. Be sure to listen to it all the way through, because it changes significantly after the halfway point.

Concept Demo: Broken link

What kind of soundtrack do you think the game should have? A generic slice-of-life high-school anime soundtrack, with “disturbing” and “horrifying” versions of each track, depending on the player’s actions? Or something else entirely?

Progress Update

I’m sorry for not updating the blog sooner. I originally planned to update more frequently, but other events in my life have been pulling my attention away from Yandere Sim.

I’ve still been making progress at the game, just not at the same speed as before. I’ve got some new features in. They’re not particularly exciting, but they are proof that I’m still working on the project.

I started implementing NPCs. So far, NPCs have a cone of vision, and can tell if Yandere-chan is in their cone of vision, and can tell whether or not they have direct line-of-sight with Yandere-chan. Here’s an example:


Here, the NPC confirms that Yandere-chan is in her cone of vision, but fires a raycast to obtain direct line-of-sight, and determines that Yandere-chan is hiding behind a wall. The NPC takes no action.


When Yandere-chan is nearby other NPCs, they turn to face her.


When Yandere-chan is armed and nearby an NPC, a button prompt to attack that NPC appears.


When Yandere-chan attacks an NPC, their facial expression changes, and they raise their hands in defense.


After killing an NPC, they turn into a ragdoll.


Here are some of the next features I plan to work on:

  1. NPCs should have a “fear meter” that increases when Yandere-chan is holding a weapon. The closer Yandere-chan is to the NPC, the quicker the fear meter will rise. A maximum fear meter will cause the NPC to run away in fear.
  2. Scaring an NPC causes them to spread nasty rumors about Yandere-chan, lowering her reputation at school. A low reputation will cause other NPCs to be wary of Yandere-chan. They will keep their eyes on her when she enters a room, making it more difficult to steal things or get stealth kills.
  3. If Yandere-chan’s reputation hits rock bottom, Senpai will never love her, and it’s Game Over.
  4. When an NPC is scared of Yandere-chan, they will be expecting her to attack them, so they will put up a struggle if attacked head-on. They will still die, but they will scream upon their death.
  5. When other NPCs hear a scream or another suspicious sound, one of them will walk over to investigate the source of the noise.
  6. If an NPC witnesses Yandere-chan committing a murder, they will run away from Yandere-chan until they reach a safe distance, take out their cell phone, call the police, and name Yandere-chan as the murderer.
  7. Once the police are called, they will arrive within 5 minutes. Yandere-chan has that amount of time to kill the witness, hide their body, and dispose of any evidence of her murders. If she successfully removes all evidence that a murder took place, the police will assume that the call was a prank. If a body is discovered and/or the witness is still alive, but there is no incriminating evidence, the school day will end, and Yandere-chan will be interrogated for the rest of the day. If any incriminating evidence is present, the police will arrest Yandere-chan, and it’s Game Over. With no evidence, she can’t be arrested.
  8. Yandere-chan should be able to pickpocket other students’ cell phones. This will prevent them from calling the police. Yandere-chan can also send text messages from a student’s phone in order to impersonate them.
  9. A student with no cell phone who witnesses Yandere-chan commit a murder will attempt to run out of the school, and warn other students about Yandere-chan as he runs past them. The student will run to the police station and give his eyewitness testimony to the police. The police will then head over to the school.
  10. A student who finds a dead body or a pool of blood will inform the police. The police will then head over to the school to investigate.
  11. Whenever the police arrive at school, the school day instantly ends, and the game continues on the next day.
  12. Blood should shoot out and make a puddle when Yandere-chan stabs an NPC.
  13. Yandere-chan should be able to drag dead bodies and dump them into hiding places. The blood should make a trail to the body.
  14. Yandere-chan should be able to mop up blood. (Carrying around a mop and a water bucket is not suspicious at all during cleaning time at Japanese high-schools. The best time to commit a murder?)

What do you guys think of these features? Please let me know in the comments below. How do you think these components of the game should work? How should students react to the various things they can witness or discover? How would you design it?

Main character concept art

It’s important to me to make sure that the game’s protagonist has a unique and memorable appearance. I’d like her to be easily recognizable so that people can say, “Oh, I know that character, I know what game she’s from!” and tell her apart from other anime girls. I’d like Yandere-chan to be the “face” of the game, appear in the promotional art, etc.

I’ve teamed up with a talented artist who goes by the name of “aea” to produce some character designs for the game. I’m not sure how many revisions we’ll go through before we nail the final look of the main character, but I think the first draft looks absolutely awesome, so I wanted to share it:


I’m hoping to wind up with a character who has a signature trait that makes her easy to identify; her personal trademark. I asked aea to design a character with unique silhouette, and in this design, he’s given her tufts of hair on her head that resemble horns, or perhaps bobcat ears. It definitely achieves the desired effect; I can’t think of another character she could be mistaken for!

The “horns” also carry the added bonus of making her look slightly devilish, which suits a serial killer. However, is that too on-the-nose? “She’s a bad person, therefore she gets devil horns.” Is that how it comes across? Or, is it subtle enough to not invoke that kind of reaction?

My philosophy towards the school uniform is the same as my thought process regarding the character; I want it to be unique from other school uniforms, so that people can instantly recognize what game it’s from when they see it.

I’d like to ask you what you personally think of this design. How do you imagine this character? How do you think she should look? Keep in mind that her primary objective is to be stealthy and inconspicuous. With that in mind, should she look as plain and non-threatening as possible? Or would a sinister, almost “predatory” appearance suit a stealth game about hunting and killing? I think this design strikes a nice balance between the two – but what do you think? What would you change about it?

What does this mean for character customization?

My desire to have a main character with a memorable appearance runs contrary to the concept of allowing the player to customize the character and design his own Yandere-chan. I understand how fun character creation is, but I would highly prefer to give the game a “face”. Ask yourself this: If someone sees a screenshot from Yandere Sim, how will they be able to tell what game it’s from? If someone sees a customized Yandere-chan, how will they be able to recognize what character she is or what game she is from?

This doesn’t mean that character creation / customization is entirely out the window, but it’s not the option I’m currently leaning towards.

Please share your thoughts and suggestions!

Yandere Clicker Update

Please forgive me. I had so much fun making Yandere Clicker that I decided to update it.


Now you can buy upgrades to stab Senpai even more.

There’s still a lot more I could add to this game, like achievements and perks that boost the effectiveness of your upgrades, but I think I’m done working on this thing for a while. I should get back to the development of Yandere Sim now…

Yandere Clicker – A parody of Cookie Clicker


I got a little tired of working on Yandere Sim, and decided to take a little break from it by making a silly game for fun. (Actually, this thing doesn’t even qualify as a game, because you can’t win or lose…)

The only website I know that lets people upload web games is Kongregate, so I decided to upload the game there.

The idea was to make a parody of Cookie Clicker, except instead of clicking a cookie, you are a Yandere girl stabbing a dude.


  1. Be a Yandere girl
  2. Stab a dude
  3. Move the camera around to get a panty shot

If anyone thinks this game is amusing, I could update it with more features. I can add upgrades and achievements, like in Cookie Clicker. What kind of upgrades should you be able to buy, though? Hire other Yandere girls to stab for you? Upgrade your knife so each stab counts as multiple stabs?

Please note that this doesn’t mean that I’ve stopped working on the original game; I just decided to take a short break and made this for fun. This doesn’t actually hinder the development of the real game.

Information from an actual Japanese high school teacher

Last night, I had the pleasure of speaking to an actual Japanese high school teacher about high school life in Japan. I met him in a chatroom a year ago, but I never thought of asking him for details until last night. Here is some of the information that I gained from him. Please note that some of it may be exclusive to the particular Japanese high school that he works at.

First, I’ll start off with a time-table:

  • Students may arrive at school anytime from 7:30 AM to 8:30 AM.
  • Homeroom lasts from 8:30 AM to 8:40 AM.
  • There is a ten-minute prep for the next class from 8:40 AM to 8:50 AM.
  • The first class lasts from 8:50 AM to 9:40 AM.
  • There is a ten-minute prep for the next class from 9:40 AM to 9:50 AM.
  • The second class lasts from 9:50 AM to 10:40 AM.
  • There is a ten-minute prep for the next class from 10:40 AM to 10:50 AM.
  • The third class lasts from 10:50 AM to 11:40 AM.
  • There is a ten-minute prep for the next class from 11:40 AM to 11:50 AM.
  • The fourth class lasts from 11:50 AM to 12:40 PM.
  • Lunchtime lasts from 12:40 PM to 1:15 PM.
  • There is a ten-minute prep for the next class from 1:15 PM to 1:25 PM.
  • The fifth class lasts from 1:25 PM to 2:15 PM.
  • There is a ten-minute prep for the next class from 2:15 PM to 2:25 PM.
  • The sixth class lasts from 2:25 PM to 3:15 PM.
  • Students clean up the school from 3:15 PM to 3:30 PM.
  • There is one final Homeroom class from 3:30 PM to 3:45 PM.
  • At this point, students are free to leave and go home, or stick around and do club activities.
  • During summer, the school closes at 6:00 PM. During winter, the school closes at 4:00 PM.

If we want to go full school simulation, then the game would follow a schedule exactly like this one.

In some Japanese high schools, the students stay in one classroom, and the teachers change classes. This would mean that the 10-minute gaps between classes are not playable sequences where you can walk around the school. This would mean that the only time you’re able to walk around the school is for 60 minutes before classes begin, 35 minutes during lunchtime, 15 minutes during clean-up time, and 135 minutes after school.

If we choose to set this game in a school where the students have to change classes during those 10-minute gaps, then there are potentially 6 more opportunities to walk around the school, but for much shorter periods of time.

Which would you prefer? Would you prefer ten or more opportunities to walk around the school throughout the day? Or would you prefer four chances to walk around the school? Do you think it would be best if the player is only allowed to walk around the school during club time, since that is the longest period of time that students can freely wander around the school?

I was also sure to ask him what is suspicious and what isn’t suspicious to see a student doing.

  • It’s not suspicious for a student to wander around the school at lunchtime.
  • It’s not suspicious for a student to wander around the school during clean-up time carrying around a trashcan (which may be used to transport a dangerous weapon that would otherwise raise suspicion).
  • It’s not suspicious for a student to wander around the school during club time even if they’re not in a club. Many students stick around at school to study, or do their homework.
  • Nobody would bat an eye if they saw a student carrying around a large case during club time (bokken case, guitar case, kyudo case). But if the student is sufficiently popular, then other students may know which club she belongs in and what kind of case she should / should not be carrying around. Other students from that club would also know who should and shouldn’t carry around a specific type of case.

Other details:

  • Students are expected to bring their own lunches to school. There are no cafeterias in Japanese high schools, although sometimes a local bakery will set up a stall somewhere in the school during lunch and sell various baked goods. Students can eat lunch anywhere they want as long as they are not obstructing anyone.
  • Japanese schools don’t have hall monitors.
  • Japanese schools don’t have janitors. The students are responsible for keeping the school clean. However, there is a groundskeeper, whose job is to take care of tasks that are too big for students, such as gardening work and performing repairs on the building.
  • Japanese schools are extremely strict on truancy and tardiness. Attendance is monitored very carefully, and any absence will be noted very quickly.
  • The entrance to a Japanese school has shoe lockers where students swap out their normal walking shoes for indoor shoes. Some Japanese schools also have small lockers for books outside of classrooms.
  • Even though it’s not common to see in anime, Japanese students in real life do wear back packs, although this may vary from school to school.

He also pointed out another important detail. These are middle-school outfits:


And these are high-school outfits:



So, what do you think this information should mean for the game? What time(s) of day do you think the gameplay should take place? Should the player be allowed to take every possible opportunity between classes to set up traps, steal things, conceal and move weaponry, and socially sabotage their classmates? Or should the player be given a small number of opportunities to move around for a long period of time, such as the lunch time-frame and the club activity time-frame?

Inventory and Weapons – How do you think I should proceed?

I’m sorry for not updating during the last few days. I was improving the controls and the camera, and that’s worth posting about, because it doesn’t look exciting or interesting in a screenshot. I also got the cover system working.

Today, I added the ability to find weapons, equip them, and store up to 3 of them in an inventory.

Here’s what the inventory looks like:


I’m not sure if it should go in the center of the screen…


…or on the side.


When you are using a Keyboard to play the game, the Inventory interface will look different.


This inventory is not necessarily the final design; I just threw it together because I needed a graphical interface to use while getting the weapons to function. Perhaps it would be a better idea to use an entirely different kind of inventory; perhaps a “Tetris Style” inventory like in Resident Evil 4, so the player can have fun organizing their weapons?

When you are nearby a weapon, a faint button prompt will appear over it, along with its name. When you are close enough to pick it up, the prompt and name become clear to let you know that you are currently highlighting that weapon.


If you are already carrying a weapon of that “Type”, the game will tell you that you’re going to be swapping one weapon for another.


This brings us to a quandary that I’ve run into…

I need your help!

I’m having trouble deciding how to categorize the weapons. I originally planned to categorize them based on how they are used (stabbing, slashing, or bludgeoning) but then I started wondering if it would make more sense if the weapons were categorized according to how suspicious they are. Some weapons look harmless and can be carried openly without arousing suspicion (scissors, screwdriver, hammer), but other weapons look threatening and will instantly alarm people (knife, syringe, hand-axe). Another option is to categorize the weapons by size (small, medium, or large).

The reason I need to know how to categorize the weapons is because it will determine how I should handle the game’s inventory. If the player finds two weapons of the same type (scissors and screwdriver, both are small and inconspicuous stabbing weapons), for what purpose would the player want to pick up both of them? Should I allow the player to carry around multiple weapons of a single type, or disallow it?

I’m also not sure how many weapons the main character should be able to hold. How many weapons is too many for a schoolgirl to carry, before you can’t suspend your disbelief anymore? Or is a Yandere game already so silly that I shouldn’t bother keeping the inventory realistic?

If you’re interested in helping out, please give me your opinion on these topics:

  • How do you think the inventory should work?
  • Where should the inventory appear on the screen?
  • How do you think I should categorize the different weapons of the game? By how conspicuous they are? By their size? By how they are used in combat?
  • How many weapons should the player be able to carry?
  • Should I allow the player to carry around multiple weapons that all have identical functionality? (Or multiple weapons of the same “type”?)