A downloadable game for Windows, macOS, and Linux

Buy Now$19.95 USD or more


Quantum Suicide is a game of betrayal, deception and romance in the cold depths of space.

This science fiction thriller tells the tale of an intergenerational mission and its diverse crew, fighting against a deadly AI (and each other) for the chance to survive. Strategy, love interests and quantum mechanics await you. Your choices change the fate of everyone in Quantum Suicide.







Quantum Suicide is a Japanese-style Visual Novel set in space. You play as a researcher aboard a spaceship on an epic mission to find humanity a new home. The mission is jeopardized by a corrupted A.I system that forces you to play "The Deletion Game", a weekly game where you must battle your crew mates for survival. Prepare to make both friends and enemies of your crew members as you play through a series of Deletion Game puzzles. Can you see the Everett's mission through to the end...alive?

An example of the puzzles you can expect (パズルの例):

Quantum Suicide contains 6 courtable options (3 females, 3 males). With their own hopes, desires, personalities, and sexual preferences, you will have to move carefully to earn each character's affections. Each courtable character has at least three posed sprites, each with multiple facial expressions. In addition, all characters are partially voiced by professional Japanese voice actors. Boasting over 30+ hours of gameplay, you must navigate your way through over 30 different endings, including bad, good, and true endings for all courtable options.

  • Play as a Boy or a Girl
  • 女性か男性を選び、星をナビゲート
  • 7 Courtable Options (3 Male, 3 Female)
  • 選べる7人のキャラクター
  • Courtable Options Have Their Own Sexual Preferences
  • 選べる7人のキャラクターは恋愛の好みもそれぞれ
  • Including 6 chapters and over 30 Different Endings
  • 全6章と30種類以上の違うエンディングが登場。
  • Available in English and Japanese, with Voice acting.
  • 音声はもちろん、各操作は英語と日本語の2カ国語に対応。

*Note: Quantum Suicide does not follow traditional dating simulator/game structure of a point of flag system - outcomes are based on character deaths. Just a head ups to avoid disappointment in the system :D

*I am also still supporting the game and pushing updates/patches - so please use the itch.io app for your convenience! And feel free to message me with any problems/bugs and I will attempt to fix them asap!*

To check your game is up to date, from the main menu, please select Extras > Credits and then in the bottom left hand corner is should read: Version: 29.10.211 (if it doesn't, you are not up to date!)


Buy Now$19.95 USD or more

In order to download this game you must purchase it at or above the minimum price of $19.95 USD. You will get access to the following files:

Quantum Suicide 4 GB
Version 7

Download demo

Full Voiced Quantum Suicide Demo. 443 MB
日本語の体験版のダウンロード 198 MB
Quantum Suicide Demo - MAC AND LINUX 471 MB

Development log

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Viewing most recent comments 11 to 50 of 91 · Next page · Last page

Hello! I'm a Chinese translator/localizer. I am very interested in this game and I'd like to be hired to translate this game into Chinese. Would you like to work with me?



I am unable to get my game to the latest version. I am only able to get it to version 29.10.221. Any suggestions? 

Hi Zilli!

I am so so sorry for this mix up - but it appears I made a typo on the main page - 29.10.221 is the latest version! If you can play the Halloween Special in the Extras menu, then you are up to date! (I have now fixed the main page with correct version number)

Again, I am so sorry for my error and hope I haven't caused you too much trouble!

<3 MC

Thanks so much! Here I thought I was losing my mind. I love this game <3 <3 <3

I'm so glad you love it! I can't thank you enough for giving it (and me) a chance and for your kind words <3 

I love 'groundhog day / time loop' types of games, and this one was amazing. I've never played a game centered around metaphysics and quantum physics before,  but 'Quantum Suicide' managed to intertwine themes of philosophy without taking away from the characters and storyline. I earned all the CGs and experienced all of the endings, and it was worth the hours.


Hi Marquis! 

Thank you so much for playing QS and enjoying it so much! This comment has made my day :D 

I am working on future patches and updates to improve the QS experience as well as other content~ Please follow me on Twitter for the most up to date news and content! :D

<3 MoltenCherry


Of course! 

I can't imagine the logistics and process of creating such an expansive project like QS, but do you have any future projects planned or in the works? If you ever have a Patreon or Kickstarter active for new projects, I'd love to support. 


Hi Marquis!

I do have a Patreon (that I only just recently started) if you would like to check it out :) I have a few things in the works at the moment~ I do also plan to use Kickstarter again in future, once I have everything ready and set up for at least one of my future projects.

Thank you again for playing and enjoying Quantum Suicide :D

<3 MoltenCherry

P.S - If you enjoy merchandise, I am working on an online store via my website that I will launch once all the Kickstarter backer physical rewards are sent out :D

Hi! How can i get the Mac demo to run? I'm trying to open the Renpy file but it just crashes immediately.

Hi Jdogz :)

To get the MAC version to work (I am not sure if this is what you are doing, so tell me if this isn't working)

- Download the demo

- Unzip the demo (if you don't unzip it first, it will crash when trying to boot)

- Then open the file called: QuantumSuicide.app 

Hopefully this should work! Please let me know if it doesn't and I will try to get someone to test - I don't own a MAC :(

<3 MoltenCherry

Thanks for the reply!
I'm unzipping the demo like you said and opening this file:

After that I get a message saying the file can't be opened because the developer cannot be verified (which is normal and happens for anything I download on itch.io), I go to my settings to bypass this message, then when I try to open the file again it just crashes after a few seconds.

Let me know if there's something I'm doing wrong - I'm on OS Catalina by the way.

Hi Jdogz!

Sorry it still isn't working! Please leave it with me and I will try to work out a solution. :) (Sorry it may take me a few days as I need to find someone with a MAC to help me problem solve)

<3 MoltenCherry

Sorry if this question has already been asked - is there a Mac demo available?

I. . . have never been asked for a MAC demo! Give me a moment and I will put up a demo that works for Mac and Linux :D

I have put up a version of the Demo that should work on both Mac and Linux. If you try it and it doesn't work, please let me know! I don't have a Mac to test on this side :D

It works, thank you so much for replying and putting up the demo so quickly!

Uh, is the true ending restricted to the male player character. . .? I heard a rumor that you can only get the true ending as a boy. As someone who really prefers to play as a female character and hates when male is automatically just seen as the 'default' I was curious about this.


Hi HellWimp!

Thanks for your question :)

Technically, there is two true endings - one for the male route and one for the female route that are both (in a way) intertwined (and the way the game is designed, you will need to experience the game as both to achieve). Both these endings will result in the same true ending achievements and credit unlocks regardless of whether you are a boy or girl. 

Because the true routes almost need each other, I would argue that neither male or female route is default as the game was created from day one to encompass both in meaningful ways :)

I hope this helps! 

<3 MoltenCherry

P.S - an update is coming soon that will add a small amount of content to all romantic endings and true endings! :D So hopefully, they will be even better!

Does this game come with a steam key? I keep looking for it but I can't find it :( I prefer buying games on itch.io because I hate giving Valve money, but for some reason it won't extract the exe file D: Otherwise I think I'll just buy the game again on Steam! 


Hi Emi!

It doesn't come with a Steam key - and I am sorry that it isn't extracting for you! This being said, if you want to email me proof you have bought the game on Itch (cottoncandycyanide(at)gmail.com), I will send you a Steam key! :) You shouldn't have to buy the game twice when one isn't working~ (also, if you could send a screenshot of what is happening when trying to extract so I can try to troubleshoot for future players, I would super appreciate that too! :D) 

<3 MoltenCherry

I'm literally an idiot, I tried extracting it again to get the error message to pop up and it worked this time, for some reason? So everything's fine! Thank you so much for your quick reply!! 


Not at all! These things happen! I am just super glad it is working now :) I will have a major patch coming in the next week or two so please let me know if that doesn't work or you have problems :)


I remember playing the demo for this about a thousand years ago (what is time) and was excited to see the real thing come out. I binged the whole thing in a few days. Just wanted to say thanks for a fun time!

Hi Ghost Clown!
I am so glad you enjoyed it! 

After some feedback, I will be adding some more content to the romantic endings to give a better glimpse into the future :) These should be put in in November~ When I add these, simply start from the timeline to see the extended endings (If you want to!) 

<3 MoltenCherry

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hey! id like to ask if this game is still coming to the vita. i'd much rather play it there. either way, great work from you. glad to see that you're helping people solve their issues with bugs in the game and patching in fixes. <3

Hi Brookdortz!

I am just working that out at the moment - but it doesn't look good ><'. It will take me about 6 months to make it work on Vita and would appear at best to get about 150-200 people to play~ Soooooo, maybe I will make for Switch and PS4 instead ><' Sorry if this disappoints! I am still not at a stage in which I get paid, so it's hard to put in the hours on top of other work I do to pay the bills :D

Hope you understand! :(

<3 MoltenCherry

Hey! I'm currently playing the game and am loving it so far (Katashi is the love of my life)! I'll make sure to leave a review once I am further into the game. While I've been playing I've been screenshotting some bugs I've noticed, nothing major just small little things. I was wondering if you would like to know of these bugs, and if so what the easiest way would be of getting them to you?

Keep up the awesome work man! I can't believe you are patching every week or so, that is some serious dedication. Make sure to take care of yourself and don't let the negative comments get you down, the fact this game exists is a phenomenal achievement (also it is very, very fun)!

Best of luck!

- Booker

Hey Booker!

Thanks for the comment and the ongoing support <3

If you have any bugs or weird happenings you have noticed (and am willing to spend the time), please email me your screenshots and explanations (in case it isn't clear) and I will do my best to get on top of them! After all, everyone would prefer a better polished game :D

You can send me the screenshots here:


The next patch/update should be live later today! :D

Thank you again for your kind words! It is very easy to let the negative get on top of you so I appreciate you taking the time to be so kind~


(1 edit)

Awesome! I'll make sure to do that after I check which bugs have been fixed through this update (it seems like a couple from what the update log stated!). But I've updated the game on Steam and received this at start up

And here is the traceback log

I can get the game working by selecting the boxes below the DirectX, but this seems to also revert it back to it's previous version, not sure though? Unsure what's causing this but thought you'd like to know!

- Booker

Hi Booker!

I had a similar issue occur. However, I just closed it and tried to reopen it again through Steam and it appeared to work (I am not sure what is happening). If you go to your save files, do you only have 6 or is there an arrow pointing to the right?


I've got the extra save files, hazzah! Everything seems to be working perfectly, I also adore all the new sound effects. Currently 14 hours in and I'm absolutely in love! I even streamed it on discord with a friend while they were downloading their own copy, he was making fun of me for being so stressed at all the decision points because I was trying so hard to make sure Katashi didn't die. But It seems like his feeling the stress playing it himself, so fairs fair. I've also roped a couple other friends into buying the game as well, so woohoo! Also super hyped for the revamped romance endings, you just keep out doing yourself ever update, I swear.

Sorry for the long rambly reply, just really excited about this game right now! I once again wish you the best of luck and hope you are doing well! I had the honour of meeting you at PAX Aus last year and you were super lovely, so I will do my best to return the favour. 

Great work!

- Booker

Deleted 2 years ago

Hi Exiisable!!

Thank you so much for your review! (Also, I am incredibly curious as to what happened last time your reviewed on Steam! If this review was a demo, I just bought your game to find out more :P)

I am glad you enjoyed all of the characters and your comment on Katashi's death make me laugh a little - He just can't help looking that good, even in death :P

As for your comment on the endings, I agree with you. The endings ended up as the same formula mainly due to a resources issue. The game was out of money shortly after the legal troubles and so I have been funding it with part time jobs and scholarships for almost 2 years - I know this won't make up for it, but I am in the process of creating extended romance endings - similar to the friendship ones - to give you a snippet into the future and hopefully make the endings feel even just a little more fulfilling. These should be patched in in the coming weeks :)

This is the first game I have ever made, and so your feedback, especially on the endings, is super helpful! I hope that with this experience, I can only make better games for you all <3 I hope you look forward to playing them as much as I am to make them!

Other than following me here (to get progress on work and news etc), I also have a Twitter account and have started a Patreon in the last month! 

Standby for the extended endings and I hope you enjoy the girls side just as much! (I look forward to your updated review!)

<3 MoltenCherry


I just played the game and got stuck at the end of Nikolai's route when we must find the code to neutralize DAI. I looked in our community hub and someone said it was "through the harships to the stars". I tried four times with no succes, do I have to go through other routes before trying again ?

Hi Pluie!

I don't want to give any hard spoilers, so I will be saying all this weirdly. . .

To get the password, ideally, you need to find pieces of the code throughout the timelines.

This being said - what you have attempted to use as a password is wrong, but not suuuuper wrong.

Once you have the password correct, it will work on every timeline - there is no requirement to clear other timelines (other than to get the clues) - which, if you look up the answer, you can bypass :)

I hope this has helped without ruining anything for you or others!

<3 MC

Thank you !

(2 edits)

When I first found out this game I was so happy I found a game that is just a little similiar to my beloved Danganronpa. And I'm so happy this game finally got its final version!

I must admit that sometimes change in sprite "drawing style" bothers me - some sprites look more qualitative than the others. But it's probably because I'm a perfectionist, so it's nothing that big. Especially when I like both "drawing styles" (I don't know how should I name it).

The only real complain I have is that I cannot pick the English dub in the settings. I certainly can pick the dialogue language, but it's not possible to change voice acting to English. Fortunately, I was going to play the game in this way (with Japanese voice acting, that is) but I would like to play it with English dub, too.

Also, I wanted to add I really love this reference to Danganronpa. Seeing it is like honey in my DR-lover heart.

Oh, and by the way - I remember I saw a version of this game called a "Everett's Christmas" (or something like that) on this site before. Does the fact that it's not here to download anymore mean it will be no longer available to play or do you maybe plan to make it a DLC or something like that? I wanted to play that version, but I promised to myself that I will do it only after beating the full game. It would be a pity if it was gone forever.

Hi RainbowCarp!

Thanks for your message and your appreciation for the Danganronpa- homage :P

As for the VA not changing - Is this what isn't working? (See video of me changing the VA - this video is a recording of the itch.io client version!)

(Ignore the terrible screen - I just opened OBS quickly to record this so I can troubleshoot your problem~)

Please let me know so I can try to fix asap for you :)

As for Christmas Everett - I maaaaaaaaybe cleaning it up with plans for a re-release as an inclusion later in the year :P So please don't fret too much :D


Yes, that's exactly it! But for some reason in my version of the game it looks like this

and no matter which option I choose the voice acting always is in Japanese.

I don't know if has any meaning, but bought the game by Steam.

Good luck with the project!


Just checked Steam version and it also appears to be working - however - there has been more than one patch on Steam. So if it isn't too much trouble, could you please sign out of Steam and back in? For some reason, QS doesn't auto update for some people - hopefully when you log back in you will have a patch to download and it will fix it :) 

Please let me know how it goes! 


So... I don't really know where to put this, but-
Despite not lying to Sora+Vlad, when I get to the first Deletion Game choice, when choosing a certain option, the game behaves as if I had lied, and the only other options are to come clean or keep lying. I bought the game here, so maybe this bug was fixed in the steam version, but wasn't for the itch version?

Argh! Thank you for this report!

I have attempted to fix it now twice, and it works on my end, and for some reason no matter what I am doing, it still bugs out when others play! I will take this and attempt for a third time to get this achievement working for the next coming patch :)

Thank you so much for taking the time xeb to let me know about this! This bug haunts my dreams :P

<3 MoltenCherry

Also - this is just an achievement error and won't affect the rest of your game :D (and the versions are the same - sooooo the Steam one is also broken still T.T)


Well, I hope you enjoy it <3

Is there a guide?

(1 edit)

There isn't an official guide just yet, however, some of the players over on Steam have made threads helping with bits and pieces that might have what you are looking for at this point! You can find that here!

I will work on making an official guide and walkthrough! 




I'm very much aware that this is just me being weak, but... I don't have the time for a ton of replays on my hands anymore. So I kept save games (about 1h of playtime's worth, roughly), but somehow I maneuvered myself into a bad end I couldn't get out of by loading them. Guess I got rid of the wrong persons in the first two rounds (though I managed to pick them just as I intended to).

Too bad there aren't more save game slots (pages? where are they?)...

Even googling "that code" didn't work for me. Lower case still didn't. Guess I'm not qualified at that point in the VN.

So I fear I'm out. I understand failing might just be an intended part of the experience, but this isn't FTL or Into the Breach, so I'd need to invest too much time. Heck, if even cheating can't get me there, then what? ;) Too frustrating to keep going.

Seems I'm the kinetic novel kind of person, branching ones just don't suit me...

Just wanted to play once and get some nice Yuri ending despite the horror. Guess that didn't work out for me. :( Picked the wrong VN. My fault, naturally, so future playreaders, take this (negative) comment of mine with a grain of salt. This VN might still be for you. Just isn't for me.

PS.: Don't hate me! It's just: I came here for Yuri, and left because of the pain. ;)


Hey Thrawn!

Thanks for your comment and I'm sorry it wasn't for you :( The game does ask for a fair amount of your time and does have many bad endings for you to accidentally end up on T.T

I only included 6 slave slots because of the inclusion of a time line function, but I hear you!! I will work on adding more save slots today and patch it in within the week! So thank you for that! So even if you won't use them, know your input has made future players experience better :D

Again, I am sorry it wasn't for you, but reaaaaly appreciate you giving it a shot!

<3 MoltenCherry

I just get frustrated far too easily these days I guess. ;)


We are live! I hope you all like it (T_T)<3


I really do hope you like it!! I will be doing patches and updates in the coming weeks, so it only looks to get better :D

(1 edit)

dude.... this game is perfect

T.T <3

Sweet I can't wait until the full release of the game. I told my friend about this and she might play it one day

Will be out on the 10th of October!! :D Thanks for spreading the word~

Are there any plans to bring the full game to Itch.io ?


Hey there Public Lewness :D (Great name by the way!)

I have just received approval for the games large size to be uploaded and am just working out the system to upload and patch when needed :) Should be up sometime this week and when it is, I will do an announcement <3 Sorry for the delay!

Awesome news ! count me in for a purchase when it's ready.

I was wondering if I am OK to stream this game on Twitch, and whether there are any spoilery parts I should avoid recording? 

So is this game still coming out? Just wanna know since I'm really invested in it

It released yesterday on Steam - as a backer, haven't heard anything about an itch.io release yet so probably best to buy it on there!

Hey Aretsu!
It is still coming to itch.io, however, due to it's size I wasn't able to upload it and have to go through itch.io support. I am awaiting their help :)

Sorry for the delay! It is my first time putting a game up of this size and I didn't realise it might take days to get approval/assistance :(

Thank you so much!!

Loved the game!!!! I finally found something like Danganronpa.

AAaAaAaAh. NECESITO JUGAR ESTA MARAVILLA, el problema es que mi ingles da para poco y el japones ni verlo, vaya lastima espero que los creadores lo traduzcan al español o que al menos den consentimiento a alguun traductor para poder entender esta preciosidad de juego.

(Esto está traducido por computadora, lo siento pero no puedo hablar español) ¡Esperamos que el juego sea lo suficientemente exitoso como para poder financiar traducciones de calidad en el futuro, incluido el español! :) 

I love this game so much and can't wait for its full release!

I only have one question - do you (the creators of this game) plan to translate this game on other languages (other than English/Japanese)?

At this point in time, English and Japanese - however, depending on the response, I am very interested to get into other languages! The biggest hurdle is the cost :( 300,000 words are not cheap when looking for a quality translation :)

I see.
Also, if you ever needed a volunteer in making Polish translation to your game, I would be glad to help you.
In truth, I'm not a professional translator, but I'm interested in translating games & they say I'm good at both English and Polish (which is my native language). And I love to help with projects! Also, I'm a perfectionist, so I would make sure to make a quality translation.
But I understand if you prefer a professional translator or don't consider making Polish translation to your game in the first place.
Either way, I hope this game will success!
Have a nice day!

Played the demo, I'm so excited to see a full release! This was amazing!

Quantum Suicide looks very intriguing.  Is the beta testing finished or almost done?


Almost finished! We are hoping to have the game out at the end of the month! We are so sorry it has been delayed due to illness :( 


I'm ssooo excited for the full gameeeee!!!!!!!!!!!!! you guys did amazing


are we gonna have to pay to download this when it is completed? i really hope not...


why not? I would gladly pay for a good game! And am Very excited!

Deleted 1 year ago

very sad! I understand the broke life. Up to the devs! But I fell the devs should be rewarded for their work!

i belive they should charge for this game if it's gonna be good, they deserve it!


So this is just Danganronpa with sex


I wish that was true! But unfortunately, there are no sex scenes. The game only has 'suggestive themes' and is relatively kid friendly - well, as kid friendly as murder can be :D

thank you, i wasn't sure whether it was okay for me to play or not

Where is it on android? 😔

Its not available yet on mobile platforms - but we will look into porting once the PC and MAC versions are release :)


I will say one of the main things for really loving this game, is the art for the female prog. Cause it looks like it got a bit lazy and just put long hair on the male face. She looks so manly.

can we eventually (rubbish at spelling so correct me if im wrong) get a port of the game onto steam after completion

As in release the game on the Steam platform? It is planned for the same time as Itch.io. You can find the Steam page Here

If that is not what you are asking, I am so sorry I have misunderstood!

Can't wait for the game's release!

Shizuka best girl until proven otherwise (as in when she backstabs me, but she'll still be best girl).

Key word to take from there is when, not if.

I feel like almost everyone can backstab you, but I'll have to wait and see :)

Moltencherry, have you ever seen the movie Primer?  It is a very interesting film that shares a certain scientificish story feature in common with Quantum Suicide (not sure if too spoilery to directly say what it is).


Hey Platonic Forms!

I have not - however, upon googling it, that will change within 24 hours :P Thanks for the question and the movie suggestion <3 

Deleted 35 days ago

104 days ago eh? fashionably late reply?

Thanks Robinicus! I am glad you like the look of it, and I hope, you will love the final product! PAX was good fun! Hope to see you again in 2019 PAX <3

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