---
title: "Gyakushuu ~Seiheki no Bigaku~"
description: "Main character loses his parents in an accident and lives in his relatives family - uncle, aunt and their three daughters. He remains cold to the family and eve"
image: "https://t.vndb.org/cv/25/26125.jpg"
---

# Gyakushuu ~Seiheki no Bigaku~

![Gyakushuu ~Seiheki no Bigaku~](https://t.vndb.org/cv/25/26125.jpg)

**Alternative Title:** 逆醜～性癖の美学～

**Developer:** Curious

**Release date:** Sep 5, 2003

**Platform:** Windows

**Language:** Japanese

## Description
Main character loses his parents in an accident and lives in his relatives family - uncle, aunt and their three daughters. He remains cold to the family and eventually starts to be treated as a housekeeper. The only joy for him is internet. One day he molests a weak girl in the train. With first crime remaining unpunished, he sets up insult hell for his three new sisters...

[From [vndbreview](https://vndbreview.blogspot.com/2019/06/vn-of-month-september-2003-crosschannel.html)]

## Characters
### Shidou Kazuma (椎堂 和真)
- **Gender:** Male
- **Aliases:** トロン, tron, 居候, Isourou, 長男クン, Chounan-kun, 電気丸, denkimaru
- **Hair:** Brown, Short, Spiky Bangs
- **Body:** Slim, Pale, Young-adult
- **Clothes:** Trousers, Sports Shoes, Polo Shirt
- **Role:** Orphan, Cousin, Roommate, University Student, Nameable, E-Friend
- **Engages in:** Cooking, Planning, Molesting, Cleaning, Blackmail, Computering, Online Chatting
- **Eyes:** Hidden
- **Personality:** Hetare, Boku, Sharp-tongued, Closet Pervert, Gloomy
- **Subject of:** Bullying, Blackmail, Teasing, Turndown

### Kagurazaka Sakurako (神楽坂 桜子)
- **Gender:** Female
- **Hair:** Brown, Long, Blunt Bangs, Sidehair
- **Eyes:** Brown, Tareme
- **Body:** Teen, Slim, Pale, Medium Breasts
- **Clothes:** School Uniform, Ribbon Tie, Pleated Skirt, Sleeveless Sweater
- **Role:** Student
- **Personality:** Shy, Low Self-esteem, Timid, Strange, Taciturn, Watashi, Quiet
- **Subject of:** Bullying, Molesting, Blackmail, Teasing
- **Engages in:** Revenge, Turndown
- **Items:** Musical Instrument
- **Voiced by:** Main

### Shidou Atsumi (椎堂 和津美)
- **Gender:** Female
- **Aliases:** Atchan, アっちゃん
- **Hair:** Brown, Short, Spiky, Parted to Side, Sidehair
- **Body:** Slim, Pale, Young-adult, Medium Breasts
- **Eyes:** Blue, Tareme
- **Clothes:** Pajamas, Thigh-high Stockings, Garter Belt Stockings, Baby-doll, Slippers, Waitstaff Uniform, Chemise, Sleeveless Dress, Formal Shirt, Usamimi Headband
- **Personality:** Lazy, Selfish, Relaxed, Honest, Atashi, Closet Pervert, Promiscuous, Cheerful
- **Subject of:** Blackmail
- **Role:** Full Sister, Cousin, Roommate, Girlfriend, Not a Virgin, Management, Part-time Worker, Middle Sister
- **Engages in:** Teasing, Blackmail, Computering
- **Items:** Handbag, Baby Bottle
- **Voiced by:** Kiriyama Minae

### Shidou Kyouko (椎堂 杏子)
- **Gender:** Female
- **Hair:** Red, Short, Parted to Side, Sidehair
- **Eyes:** Brown, Hosome
- **Body:** Slim, Pale, Young-adult, Makeup, Medium Breasts
- **Personality:** Hard Worker, Modern Tsundere, Pervert, Arrogant, Serious, Grumbler, Atashi, Competitive, Sharp-tongued, Ambitious, Cruel
- **Clothes:** Necklace, Tank Top, Garter Belt Stockings, Bracelet, Skirt Suit, Baby-doll, Open Cup Bra, Chemise, Lace Band Thigh-high Stockings, Fishnet Thigh-high Stockings, Usamimi Headband
- **Engages in:** Bullying, Drinking, Teasing
- **Subject of:** Blackmail, Fixation with Former Lover
- **Role:** Full Sister, Cousin, Roommate, Not a Virgin, Executive, Older Sister
- **Items:** Diary, Baby Bottle
- **Voiced by:** Takahashi Yuuki

### Shidou Tomoe (椎堂 朋絵)
- **Gender:** Female
- **Aliases:** トモ, Tomo, 十月 マリン, Totsuki Marin
- **Hair:** Blond, Long, Wavy, Spiky Bangs, Sidehair
- **Body:** Slim, Pale, Young-adult, Big Breasts
- **Eyes:** Green, Tareme
- **Personality:** Airhead, Spoiled, Grandiose, Carefree, Rude, Immature, Third Person
- **Subject of:** Blackmail
- **Role:** Full Sister, Cousin, University Student, Exhibitionist, Younger Sister, Net Idol, Pseudonym
- **Engages in:** Teasing
- **Clothes:** Nurse Uniform, Blouse, Ribbon Tie, Ribbon Hair Tie, Baby-doll, Shimapan, Nurse's Cap, Pinafore Dress, Flight Attendant Uniform, Chemise
- **Voiced by:** Shimada Kaori

### Hikawa Saki (氷川 崎)
- **Gender:** Male
- **Hair:** Short, Spiky Bangs
- **Body:** Slim, Pale, Young-adult
- **Eyes:** Hidden
- **Personality:** Ore
- **Role:** Boyfriend
- **Items:** Video Camera

### Junsawa Mika (潤沢 美香)
- **Gender:** Female
- **Hair:** Blue, Twin Tails, Curtained, Shoulder-length, Sidehair
- **Body:** Teen, Slim, Pale, Small Breasts
- **Clothes:** School Uniform, Glasses, Ribbon Tie, Ribbon Hair Tie, Ankle Socks, Pleated Skirt
- **Role:** Student, Classmate
- **Eyes:** Red, Tareme
- **Engages in:** Bullying
- **Voiced by:** Takahashi Yuuki

## Shops
- [Official Website](https://web.archive.org/web/20041206182150/http://www.cellworks.co.jp/curious/newgame.htm)
- [Getchu](http://www.getchu.com/soft.phtml?id=30252)

## Releases
### Japanese
- **2003-09-05**: Gyakushuu ~Seiheki no Bigaku~ - [Official website](https://web.archive.org/web/20041206182150/http://www.cellworks.co.jp/curious/newgame.htm), [ErogameScape](https://erogamescape.dyndns.org/~ap2/ero/toukei_kaiseki/game.php?game=2968), [Getchu](http://www.getchu.com/soft.phtml?id=30252)

## Tags
ADV, Rape, Non-blood-related Brother/Sister Incest, Male Protagonist, Multiple Endings, Nameable Protagonist, Bondage, Reverse Rape, Group Sex of One Male and Several Females, Group Sex of One Female and Several Males, Early Sexual Content, Harem Ending, Heroine with Sexual Experience, Chikan, Hetare Protagonist, Lots of Choices, Paraphilic Infantilism, Censored Text, Heroine with Big Breasts, Sex Scene Recollection, Shimaidon Ending, Protagonist's Cousin as a Heroine, Protagonist's Non-blood-related Sister as a Heroine, Cousin Incest

## More Games from Curious
- [Gyakushuu ~Seiheki no Bigaku~](https://pinovel.net/v6445)
- [Pink Style](https://pinovel.net/v6337)
- [Imouto Reshipi <e-moterecipe>](https://pinovel.net/v5168)

---
*View the full details at [pinovel.net/v6445](https://pinovel.net/v6445).*

```json
{"@context":"https://schema.org","@type":"VideoGame","@id":"https://pinovel.net/v6445#game","name":"Gyakushuu ~Seiheki no Bigaku~","description":"Main character loses his parents in an accident and lives in his relatives family - uncle, aunt and their three daughters. He remains cold to the family and eve","url":"https://pinovel.net/v6445","image":"https://t.vndb.org/cv/25/26125.jpg","author":{"@type":"Organization","name":"Curious"}}
```