---
title: "Oo! Imouto no Ana Kyun ~Gakkou no Youmuin mo~"
description: "An adventure game with female voices in which you are to have sex with your young sister in school. The story can be played from both brother's side and young s"
image: "https://t.vndb.org/cv/33/107933.jpg"
---

# Oo! Imouto no Ana Kyun ~Gakkou no Youmuin mo~

![Oo! Imouto no Ana Kyun ~Gakkou no Youmuin mo~](https://t.vndb.org/cv/33/107933.jpg)

**Alternative Title:** おおぉ!妹の穴キュン～学校の用務員も～

**Aliases:** Oh! My sister's slit is...

**Developer:** BANANA BLUE SOFT

**Release date:** Mar 19, 2005

**Platform:** Windows

**Language:** Japanese

**Rating:** 8.0/10 (avg, 2 votes)

## Description
An adventure game with female voices in which you are to have sex with your young sister in school.
The story can be played from both brother's side and young sister's side.
It also features 2 stories of the sister getting penetrated by a school janitor. 

[From [DLSite English](http://www.dlsite.com/ecchi-eng/work/=/product_id/RE004098.html)]

## Characters
### Hikaru (ひかる)
- **Gender:** Male
- **Traits:** 

### Chiharu (ちはる)
- **Gender:** Female
- **Traits:** 
- **Voiced by:** Akatsuki Kotone

### Janitor (用務員)
- **Gender:** Male
- **Traits:** 

## Shops
- [Official Website](http://bananabluesoft.dojin.com/soft_05.htm)
- [DLsite](https://www.dlsite.com/maniax/work/=/product_id/RJ004098.html)

## Releases
### Japanese
- **2005-03-19**: Oo! Imouto no Ana Kyun ~Gakkou no Youmuin mo~ Download Edition - [Official website](http://bananabluesoft.dojin.com/soft_05.htm), [ErogameScape](https://erogamescape.dyndns.org/~ap2/ero/toukei_kaiseki/game.php?game=6433), [DLsite](https://www.dlsite.com/maniax/work/=/product_id/RJ004098.html), [Digiket](https://www.digiket.com/work/show/_data/ID=ITM0002317/), [Melonbooks.co.jp](https://www.melonbooks.co.jp/detail/detail.php?product_id=932773), [DMM](https://www.dmm.co.jp/dc/doujin/-/detail/=/cid=d_da0564/)
- **2005-03-19**: Oo! Imouto no Ana Kyun ~Gakkou no Youmuin mo~ Package Edition - [Official website](http://bananabluesoft.dojin.com/soft_05.htm), [ErogameScape](https://erogamescape.dyndns.org/~ap2/ero/toukei_kaiseki/game.php?game=6433)

## Tags
Imouto-type Heroine, Nukige, Male Protagonist, Cunnilingus, Sex with Sleepers, Sex at School, Student Protagonist, Anime-looking 3D, ADV, Vaginal Fingering, Spoons, Protagonist's Younger Sister as a Heroine, Few Choices, Rape by Others, Other Perspectives, Blood-related Brother/Sister Incest, Blackmail, Single Blowjob, Censored Text, Completely Avoidable Rape, Vaginal Object Insertion, Multiple Endings

## More Games from BANANA BLUE SOFT
- [Oo! Rusuban wa Dokidoki](https://pinovel.net/v55898)
- [Oo! Oyakodon](https://pinovel.net/v55897)
- [Yume Shokushu!](https://pinovel.net/v11873)
- [Oo! Camp de Nurunuru](https://pinovel.net/v55896)
- [Oo! Imouto no Ana Kyun ~Gakkou no Youmuin mo~](https://pinovel.net/v11872)
- [Moshi Onna no Ko ni Nattara Nani kara Yaru ka](https://pinovel.net/v27350)
- [Moshi Onna no Ko ni Nattara Nani kara Yaru ka 2 ~Lez Hen~](https://pinovel.net/v27332)
- [Moshi Onna no Ko ni Nattara Nani kara Yaru ka 3 ~Gakkou de~](https://pinovel.net/v47783)
- [Moshi Onna no Ko ni Nattara Nani kara Yaru ka ~Gaiden~ Chikatetsu Kanojo](https://pinovel.net/v47782)
- [Moshi Onna no Ko ni Nattara Nani kara Yaru ka 4 ~Kanketsu Hen~](https://pinovel.net/v47781)
- [Shin Moshi Onna no Ko ni Nattara Nani kara Yaru ka](https://pinovel.net/v47780)
- [Shin Moshi Onna no Ko ni Nattara Nani kara Yaru ka ~Danshikou Saigo no 5-kakan~](https://pinovel.net/v24894)
- [Shin Moshi Onna no Ko ni Nattara Nani kara Yaru ka ~Tonari no Ano Musume to Kai to Kai~](https://pinovel.net/v47790)
- [Shin Moshi Onna no Ko ni Nattara Nani kara Yaru ka ~Ore ga Imouto!?~](https://pinovel.net/v47791)
- [Sekirara White Paper](https://pinovel.net/v47792)

---
*View the full details at [pinovel.net/v11872](https://pinovel.net/v11872).*

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