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Game Information
Release Date
Last Update
Orig PC Gender
Adult Themes

Version: 0.3.5

The Sissy Girlfriend Experiment



The Sissy Girlfriend Experiment is an erotic game with erotic text and images. It also contains the following themes: Forced transformation, M2F, Femdom, Cuckold (optional), Cumplay (optional), BSDM (optional), Sissy, Anal sex, Group sex, and oral sex. If this kind of content isn’t allowed in your country or you find it offensive, please, stop right here.

The game is still in alpha, have patience, a lot will change. If you want something less linear with more possibilities you should wait for the beta.

- Keep in mind that this is an early version and it will improve/change over the next version.
- The game will always be for free, but patrons will have access to a few more side quests, items and early access than the free version.

- If you load an old save game, it's possible you may have some problems with the code.
- See changelog for updates.

This game will always be free, but if you can, please support me. Your support will allow me to create more content and updates. If you can’t support me as a patron and you like this game, please support me by sharing it.


About updates: Free updates usually will happen during the first week of the month and maybe a second update during the third week of the month. Join my discord to meet other players, report bugs and to know about updates: https://discord.gg/YEwFQYD

You will start with a male character living with his sister, during a special night you met an older woman which becomes your girlfriend. Slowly, she shows her real self, but when you find out what she's up to, it may be too late.
You have a friend which you talk about your personal life, but it seems your friend may have other intentions.

Sister: She's not crazy about you.

Girlfriend: She's crazy.

Friend: She/He may have other intentions.

Doctor: You'll meet him later.

Master/Mistress: You'll get one if you decide to dump the GF.

- 20 new avatar items were added to the stores: Lingerie sets, new panties and boots.
- 05 new things to do during Friday with Sister (Go out event). If you want to enjoy everything it has to offer, you should have anal sex with at least one guy before going out.
- 45 new images were added to the main part of the story.

- Fixed a bug which your makeup skills dropped to 1 after a weekend with the GF.
- Fixed the good sister bug when you pick an evil sister.

New mode: Evil Sister - Tired of having a good and nice sister? How about a bitchy and bully one? To make your life a little harder but still fun; you can have an Evil Sister. Warning: She'll humiliate you most of the time. This mode changes how she behaves and may interfere in some parts of the story. Friday night with her doesn't sound like fun anymore... (or does it?)

New system: You can turn on a new system which allows changing between a good sister and an evil one. Did you forget to do her tasks? Uh... -1 point. Did you do it badly? -1 point. Did you spend time with her, even when she's a total bitch? +1. This system is optional. Check your profile to see what the MC is thinking about her.

New update: My profile - The option "check yourself" was updated to "My profile". The new profile changes according to your choices during the story. The MC will post new info, update the status and share some thoughts. The update also adds information counting your "progress".

UI update: Sister Good/Evil.
UI update: Friendly UI start
UI update: Check yourself
UI update: You can pick what do you want to do on Friday with your sister.



New Content

- Related to nails x 3
- Related to hair x 3
- Related to body features x 3

- Kissing contest: it doesn't look what it seems...
- Sissy videos: do you want to make extra money? Easy!

0.3.2 b

New content:
- New place: Beauty Salon (Mall)
- Chat: Talk to the costumers, you'll learn new things.
- New Makeup System: Makeup, Eyes, Eyebrow.
- New Hair variety: New style, New sizes, New colors.
- Change your nail's color.
- New waxing system: Last longer or forever.
- New job: Hairstylist with 4 jobs promotions.
- Study enough material about makeup and do it yourself at home (bathroom).

- New story: The Doctor's past.

- Fixed a bug with the lips increasing.
- Fixed a bug with the "instant dick" from the DB.
- Fixed a bug with dominance/submissive status.
- Fixed a bug with the master/mistress which the story stops.
- Fixed a bug with the ending at the costume party (BF part).
- Fixed a bug related to lips change at the Clinic.
- Fixed a bug reletad to penis shrink using the DB reward.
- Fixed a bug related to the Salon job (06 hours).
- Time of study changed from 08 - 16h to 08 - 22h.
- Fixed a bug where your chest and other parts gets bigger without the final quest.

Cheat mode:
- It was requested and it's back. You'll be able to enable it when you start a new game. WARNING: If you turn it on, you won't be able to get the real endings (when it's available). Use it to test new features.



New content: Adding variety
- Finishing the story of the new Master/Mistress. You'll earn your freedom after completing A LOT of tasks. (Last version + 0.3.1 = Over 17 tasks and different things to do with your Master/Mistress. Events may change according to your master's gender).
- Your master/mistress will invite you to different events, each one with different possibilities and results, according to your fetish and choices. Did you finish the game with the master? Try with a mistress, both have different paths.
- New story: Party at the Woods: Your master/mistress will invite you to a party to test your oral skills. Things can get a little crazy...
- New story: Sex at the Gym: Your master/mistress thinks it time to take a bigger step. Time to have sex, but he/she chooses the gym. There's a lot of events going on there.
- Sex change: After you're free, your master/mistress will give you a catalyst. Talk to the Doctor if you're thinking about a sex change.
- Huge boobs: If you have a mistress and big boobs, you may find someone in the gym during an event your mistress asked you to do. Later, if you pick the right path and your fetishes are enable, you'll be able to meet this character again. If you do what she asks you to, she will reward with a catalyst to use at the Doctor.
- Added different background to the avatar.

Bugs fixed:
- Dare Board motel task, Weekend with the GF fixed a bug which doesn't allow you to go to the motel and other minor bugs.


Re-work of the avatar
- All clothes were redesigned along with the body features and the avatar itself.
- The avatar will indicate when the MC is horny, needs a shower or needs to shave.
- Added a huge variety of shoes.
- Some quests will ask for specific clothing.
- Clothes were labeled as Gym, PJ, Casual or Sexy.
- You can remove a piece of clothing in the closet, but you won't be able to return to the bedroom without setting an outfit and shoes. You can choose not to wear underwear.
- Breasts can get bigger.
- Butt system added but not working with the avatar (YET).

Cuckold Optional
- It's up to you know, you'll need to set it at the start of the game, some parts won't be available but you'll have a different path to go.
- While the cuckold is now optional, it means if you choose to turn off this content, at a specific part you will dump the GF. You'll need to find a new mistress or master. Minor spoiler: Be careful when someone asks what you're into, this will set your new lover.

Dump the GF: Are you tired of her? You'll have one opportunity to dump her (while playing with Cuckold them on). This leads to a path to pick a new mistress or master (pay attention to your choices during the story).
- 12 new mistress/master tasks related to shopping, dare board and going to places to try different things.
- 04 quests with different options and variations.
- You'll be informed when the story stops.

Images added:
- Sister Tasks
- Master/Mistress Task

- There's a slow treatment available for players who rather have a slower change.

Stats change updated:
- regular guy: that's how you'll start.
- androgynous: induced by the main story.
- sissy: induced by the main story.
- femboy: it'll change when you get small breast or small butt. You'll have the option to change the MC's name.
- girly: it'll change when your breast and butt are at least medium size.
- female: after asking the doctor for a sex change (quest wasn't implanted yet).

Miss Stranger's basement
- Skills: Sissygasm, Blowjob and Handjob will increase until 20 only.

- Fixed a bug with the Wet T-Shirt night.
- Fixed a bug at Miss Stranger's basement.


Side Stories UI added
- When you open the game, you'll have an option to play Side Stories or the main game.
- 03 Patron Side Stories: Girlfriend, Sister and Mrs. Stranger.

New Patron Quest: Mrs. Stranger
- You're doing an interview with Mrs. Stranger. You want to know about her past, but something seems wrong.

Bug Fixed
- After the Sex Shop with the Girlfriend, depending on your choice, a specific part of the story wasn't triggering making it impossible to continue. It was fixed.


Dreams were added.
- 14 weird dreams when you go to bed really horny (8 and 9).
- 56 sex dreams based on MC stats.
- Sex dreams may improve the dominant or passive path. There's a pattern.
- Wet dream: A new way to lower your horny stats.
- You can fight the wet dream if you have 15 or more MIND.

- Stats changes were modified.
- Androgynous and Sissy: Main story changes it.
- Femboy: At least 2 points on chest and 1 point on hips.
- Girly: At least 3 points on chest and 2 points on hips.
- Slut: At least 4 points on chest and 2 points on hips and 20 skill points on blowjob.
- Whore: At least 4 points on chest and 2 points on hips and 30 skill points on blowjob and 5 points on group sex.
- Bimbo: To be added.



DB rework
- User profile moved to DB, you can see it in the bedroom too.

17 new DB tasks:
- 03 about golden shower.
- 03 about cumplay.
- 02 about BDSM/Humiliation (one more will be added in the future).
- 09 based on skills and dominance.

9 old DB tasks:
- 01 removed to update (Gym photo).
- Adapted to the new code.

DB store is working
- 7 new items which you can buy with Dare points.
- 1 will be added later.

DB message
- You will be informed if you need to buy any item.
- You will be informed where to do the task.
- You will be informed if you need to increase the horny state.

- Information about how to use it and few tips to improve your skills.

New images
- Some were added other removed.

Bugs Fixed:
- The entire DB (LOL)
- Fixed a bug with the weekend with the Friend
- Fixed a bug with the layout during the weekend with the GF
- Fixed a bug with the layout during the week with the BF
- A few bad words from the early version were removed.


Main story
- Fixed the last two stories with the GF and BF.

- Dominance or Submissive: 30 archive max points depending on your choice. This will be useful for future dare board tasks and to open new paths in a future update.
- GF and BF points: can reach a max of 13 at the moment, will be useful in a future update.
- Skill, Body, and Mind: will play important roles to open new paths.

Rework of the weekend with the friend/chat and new paths.
- Three different paths: Romance with the BF and a new mistress. I've created a possible new path for those who want a different option than the GF cuckold path. The story isn't available, just the different paths so I can work on it for the next versions. Don't worry if you take any of those paths, you'll be informed it's under development and you'll be lead to the path which is working.
- Cuckold path: While you're buying a sexy outfit for the GF, you'll be able to pick a different payment, but be careful! If you don't do what you're supposed to, you'll receive a hard punishment.
- Fixed: Three weekends with the GF and two dates with the BF. There's one week with the GF which still needs to be fixed and two dates which also needs to be fixed.

12 new sister's task
- 17 different tasks according to your character's stats. If you do at least one right during the week, you'll be able to have a nice Friday night with the sister.
Friday night with the sister
- 16 random events according to your character's stats. Just do your tasks and you'll have a nice night.
- Gloryhole in the sexshop: Pick the different payment if you dare.

Fixed problem with pink contact lens and the Sexy Clothes/Underwear in the closet. Sexy Clothes are useless right now, a future update will make better use of this option.

Rework of the weekend with the friend/chat
- The weekend with the friend where the girlfriend asks you to do something different, leads to different options. If you were a good slave, you'll have a different option available aside from two which will always show. If you were a bad slave, you'll have a different option too.
- You'll see a warning telling when the updated story stops.
- Clinic: Dreams were added. You character will dream during the improvement (5 different dreams) and the treatment (only one).
- Sister is getting more friendly.
- Girlfriend is getting crazier.
- Friend can become more than a friend.

- Fixed the sissygasm in the basement. Skills are now working properly.
- Answers reversed were fixed.
- Clinic is now available after your clothes are gone. The system is working properly again and you won't have to pay for the treatment or improvement.


Rework of the 5th week - 8th
- Remember that annoying quest in her place where you have to figure it out what she wants to do? Well... It's still available, but you won't repeat it over and over again like you used to, there are now two other quests.

- Different ending: Remember when you were the perfect slave or a bad one and the girlfriend's reward/punishment only changed with a few stats? It's gone. Based on your choices, you'll have access to 7 different endings. Of course, if you give up in the three weeks or if you're the perfect slave, you'll see the same ending over and over again. Why don't you try a few different things and see what's waiting for you?

- Gym's bathroom is now working properly. Good luck with that!



New jobs and quests: Web Designer, Housekeeper, and Personal Trainer
- Web designer: work at home, start as a blogger. You may have a promotion and do something… uh… different.
- Housekeeper: work in Mrs. Stranger’s house, an old lady with a few secrets.
- Personal Trainer: work in the gym, take a shower, help someone with the weights.
- Each time you get a promotion you’ll have to make a decision.

New features at the course
- Each job has a different course. Things to do:
- Web design: improves your jobs skill each class and mind after four classes.
- Housekeeper: do you need a course? Just help your sister at home and go work with that weird old man.
- Personal Trainer: improves your job skill each class and body after four classes.
- Bathroom: Sometimes it’s nice to take a break from everything. But don’t smoke at the bathroom.
- Dare board: You already know this one, don’t you?

New features at the gym
- Gym opens every day. Things to do:
- Workout: Improves body.
- Work: You can make money as a personal trainer (and do other things too).
- Take a shower: You have a great bathroom at home, but nothing like taking a shower in a public bathroom, right?
- Dare board: You already know this one, don’t you?

New features at the park
- You can’t work out in there anymore.
- You can meditate: improves the mind.
- You can eat a pop stickle (it may be weird if you’re horny)
- Work: Mr. Stranger lives in a house near the park, you can be his housekeeper.
- Dare board: You already know this one, don’t you?

New features at the mall/closet
- Items in the stores are now divided by groups.
- Closet: same as above. You’ll auto dress your last clothe.

New settings
- Background: Start with a small advantage in any skill you want.
- Fetish: Don’t like a specific fetish? Remove it from the game. Some haven’t been implanted yet. Some will add parts to the main story while some will add different choices. It’ll be improved it.
- New UI: Cleaner, simpler and better. Bigger images.
- Auto clothes: Remember when you needed to change clothes before doing an action? It’s auto now, but you need set it once in a while for different events or if you want to change your look.

Main quest
- 1st - 4th week: Chat was improved.
- 1st week with the GF: new option added if you want to be more dominant or submissive.
- 2nd week with the GF: if you fail to steal your sister’s panties or forget to wear it when you go visit your GF, you’ll have a nice surprise.
- 3rd week shaving: If you chat with your friend at least once during this entire time, the option to shave at his/her house is now available.
- 4th week with the GF: She’ll give you three tasks to do during the week, if you fail to do one, you’ll have a different path when visiting her. If you want to be a good slave, you should do everything she says.
- If you decide not to talk with your GF during the week, random events will happen on Sunday.
- Sister’s text is more friendly and less aggressive (1st - 4th week).
- 5th week - ???: Auto clothes were fixed for most parts, since there rest of the main quest and other side quest haven’t been re-worked yet, it’s possible there are bugs and conflict with the old code and after this part, the game may be unstable.



- New Dare board UI.
- New images and videos.

- GF and BF main story options added (3 for GF 2 for BF).
- Sister's task (every Tuesday and Thursday/more in the future).
- Dare Board: You can choose which dare to do. Reward store in the future.
- Daily money changed from 5$ to 3$.
- Patreon: Sister's party quest.
- New Mall Store.

- New store: I'll add more stores in the future with different options, I think this is an important part of the game for those who enjoy customizing their character (like me).
- BF and GF quest continues with more options and possibilities to choose from: I'm going to do a few rework on old quests. I like the idea of different actions. This makes the game replayble.



- Character's look will change with more STR.
- Character's body can change with some events and options.
- Social: this will help you see when there's an event with BF or GF available.

- GF and BF main story added (2 for GF 3 for BF and 1 with both).
- Character will lower STR by -1 (Sunday to Monday).
- Eating a candy will lower HORNY by -4 and STR by -1 (if you make your mistress mad enough, you'll be punished and you'll have to find a new way to lower your HORNY).
- Youhave to wait one day to watch porn after a Sissygasm.
- Body changes using small doses of "New SiS" three times. Ask your doctor for a free exam to check how many you have.
- Playing with a female BF will give you... hmmm... A big surprise?
- Skills were removed from random events (I'm still looking for a way to balance the skills for future events).
- Do things while watching porn will increase skills.

- Doctor office: Doctor is available on monday (if you skip it, your sister will punish you - not in a good way, it will cost $$ ).
- Doctor can improve the "New SiS" (you'll get paid for it).
- Doctor can treat the "New SiS" (it's expensive...)
- If you forget to shave before seeing your GF, you'll be punished.
- There's no more game over, but there's punishment if you skip certain events.
- Sex Shop is now available (new lingerie sets and bra)
- Makeup and makeup skills.


- Player now can check the character's stats and skills, also every time you gain points, you'll see a note about it. (except Dare Board tasks and Random Events. This will change in the next version).
- Porn points will now increase according to the amount of porn the character watches.
- Character window size increased (left menu).
- A few notes were added to help the player to know what to do next.

- Playing games and taking a shower will lower your horny state by -1. This will help players to have more control over the character's intelligence while locked. Note: Shaving will still increase your horny state by +1.
- Work out in a mindless state in the gym will increase your body stats by +1 (instead of +2). Do it in the park won't add nothing.
- Go to the course in a mindless state will increase your int stats by +1 (instead of +2). Study at home won't add nothing.
- Initial money change from 20 to 35.
- Edging watching porn will increase horny by 3 instead of 2.


- Fixed a black screen with the best friend.
- Sissy porn will increase Horny by 3 and won't lose Int anymore.


- First side quest added: the first chat with the Girlfriend, you'll see an option to know more about her past. I don't want to do any spoiler here, but in the end, you'll have two new items in your closet (unavailable in the free version).



- Fixed: Closet to mobile users: an option to show and hide the avatar was added to the closet UI.

- Fixed: Problem with the gym text showing an error.

- Fixed: Sister's text while locked won't show the erection problem anymore.



Bugs and Fixes:
- Fixed: Razor can be used 3 times before buying a new one. (The option will show up in the bathroom when the body hair has grown).
- Fixed: Shower will be available you start to stink.
- Fixed: Black screen porn. The player will be able to reach sissy porn.
(Be careful: Watching Sissy porn will increase horny +3)
- Fixed: Black screen with the GF during the first week.
- Fixed: You can choose your character’s features before adding a name.
- Fixed: Working will pay less.
- Fixed: Hard to get a game over. You will see a message about it.
- Fixed: Closet problem for Firefox users solved.
- Fixed: A LOT of grammar mistake fixed (some may still be present).
- Fixed: Panties are showing correctly during the GF’s game.
- Fixed: GF will still ask you not to masturbate, but it’s your choice now. (Unless you’re locked or during her stories).

New features:
- Added: Day counter added to the UI.
- Added: The Daring Board (computer): a new mini-game.
- Added: Text to the UI about the hair growing.

The Daring Board:
- 8 random quests.
- The option will be available if you’re mindless.
- Success varies in each quest, some depend on luck, other on your attributes.
- Quests are random, some will repeat, but some with different results and events.



- Problem with the closet while using Firefox fixed. The closet should work fine now.

Latest Reviews - View All Reviews

Review by Noknet

Version reviewed: 0.3.3 on 04/05/2019

Whether you like this game pretty much comes down to taste.  The previous reviewer said that this is slow transformation done right.  All I can say to that is "if you say so".  I lost interest before any transformation began (about the "shave all your body hair off" stage).

Review by anonymouslylurking

Version reviewed: 0.3.2 on 03/19/2019

This is slow transformation done right. The main character actually makes it feel like this is something he has to deal with. The options are always there, the whole way, to either embrace it or fight it. It's very well thought out.

I did notice a couple of bugs though.

1. For some reason, the "Makeup" skill reset sometime around when it hit level 30.

2. Time tracking seemed a bit... off.

3. There are a couple of wild goose chases. Mainly involving the "catalysts." The woman never seems to appear at the Gym, and once the mistress gives you the other, the option to use it still doesn't unlock.

4. Pink dye is unusable.


Now, for my wishlist.

1. A lot more of the same. The only reason I stopped playing is I reached the end of current content.

2. Some indication right on the main dare board screen when there are prerequisites or requirements. If not there, then within the choice itself. I reached endgame without doing the redhead trap picture shoot, and couldn't do it because I focused on growing breasts for one of the other shoots. I felt the lack of completion.

That means something though. When someone goes, "Oh man, I missed content!" You're onto a winner.

Review by pingguo

Version reviewed: 0.2.7 on 01/18/2019

This is getting better.

The last time I gave this one a try (version 0.2.1), it was a good concept with an above average presentation and a messy logistic. It was a good story disguised as a game.

This time when I checked it, the presentation has definitely improved, cutting out many of the unfriendly ui and boring items. There are new bits and pieces that are giving it life, making it gamable.

It is definitely on the right track to take off. I am having my fingers crossed.


Review by Volendi

Version reviewed: 0.2.2 on 12/03/2018

Got all the way to the end of current content, at least on one story path... idk if there are others, but it was good!  (got to the end of the "adopted as semi-little sister" route, not telling with who...) Hoping to see more!  It sucked me in, to where I actually felt invested in the character!  Seriously, really good, with a crud-ton of potential!  =^_^=

Review by Dracornis

Version reviewed: 0.2.2 on 12/02/2018

I like what is there..

But i hope for more bdsm-pictures and features in the future :)

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