---
title: "Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~"
description: "Ryuuya has an older sister, Miya. He lives a peaceful school life with his friends. But one day, he and his friends accidentally drink a medicine juice. Once yo"
image: "https://t.vndb.org/cv/01/69501.jpg"
---

# Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~

![Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~](https://t.vndb.org/cv/01/69501.jpg)

**Alternative Title:** おっぱいハート～彼女はケダモノ発情期ッ!?～

**Developer:** BISHOP

**Release date:** Feb 26, 2010

**Platform:** Windows, DVD, PSP

**Language:** Japanese, Chinese (simplified), English

**Rating:** 7.1/10 (126 votes)

## Description
Ryuuya has an older sister, Miya. He lives a peaceful school life with his friends. But one day, he and his friends accidentally drink a medicine juice. Once you drink it, you'll become sexually sensitive and get sexually excited soon. Especially the breasts of the girls who drink it will get bigger and they will need to have sex to cool down. Also, to make a vaccine, they will need to get pregnant. Like this, Ryuuya starts having sex with the girls to cool them down and make a vaccine...!

[From ErogeShop]

## Characters
### Akino Ryuuya (秋野 龍也)
The main protagonist. A schoolboy who is faithful to his own desire. He has an optimistic attitude. He is also a huge fan of animal fetishism. He is good at housework due to his parents being away often, and Miya is useless at them.
He affectionately refer to Miya as his 'No-good' sister, but he is fond of her and lends a hand whenever she is in trouble.
Natsuki is a friend of his sister, so they interact often.
Mari is a close friend of his.
Umi is like a little sister to him.

- **Gender:** Male
- **Aliases:** Ryuu-kun, 龍くん
- **Hair:** Brown, Short, Straight, Spiky Bangs, Pubic Hair
- **Body:** Teen, Slim, Pale, Large Penis
- **Clothes:** School Uniform, T-shirt, Jeans, Swim Shorts
- **Engages in:** Cooking
- **Eyes:** Black
- **Personality:** Pervert, Optimist
- **Role:** Friend, Non-blood-related Brother, Classmate, Kouhai, High School Student, Younger Brother

### Aiba Matsuri (相葉 茉莉)
The protagonist's classmate and mischievous friend.
She is a cheerful and spirited girl who can makes friends with anyone, but she is a natural prankster that often get into a bad mood.
She is not treated like a girl due to her noisy nature and tendency to make crude jokes. She is outwardly cheerful and yet naive on the inside. 
She has feeling for the protagonist deep down, and wants to be seen as a girl despite her thinking otherwise.

- **Gender:** Female
- **Measurements:** Height: 158cm, Bust-Waist-Hips: 85-60-87cm, C cup
- **Hair:** Ahoge, Short, Straight, Green, Intake, V Bangs, Pubic Hair
- **Body:** Teen, Slim, Pale, Big Breasts
- **Eyes:** Amber
- **Clothes:** Apron, Headband, Jacket, Necktie, T-shirt, Evening Gloves, Sports Shoes, Knee-high Socks, Thigh-high Stockings, Belt, Bra, Ankle Socks, Old Type School Swimsuit, Pleated Skirt, Spaulders, Sailor School Uniform, Cheerleading Uniform, Lace Lingerie, Knee-high Boots, High Heeled Boots, Short Shorts
- **Personality:** Friendly, Tomboy, Energetic, Mischievous
- **Role:** Student Council Member, Cheerleader, Classmate, High School Student
- **Subject of:** Pregnancy, Breast Expansion
- **Engages in:** Lactation
- **Voiced by:** Aoba Ringo

### Akino Miya (秋野 美弥)
The protagonist's older step-sister, who is one year older than hi,
She is the ultimate older sister who spoils the protagonist. She doesn't have much skills in most things, and relies on the MC to do the housework most of the time.
She is no-good at studying and exercise, and is a girl who fails at most of the things she does.
She doesn't have much to offer, but she is a hard-worker despite it all.
She is honest, gullible, and insensitive to many things. However, she sense that the MC is hiding something.

- **Gender:** Female
- **Aliases:** Dame-nee, ダメ姉
- **Measurements:** Height: 154cm, Bust-Waist-Hips: 87-57-86cm, E cup
- **Hair:** Pink, Ahoge, Waist Length+, Straight, Parted in Middle, Hair Beads, Twin Braids, Tiny Braid
- **Body:** Teen, Slim, Pale, Big Breasts
- **Personality:** Hard Worker, Hetare, Airhead, Naive, Honest, Brother Complex
- **Eyes:** Green
- **Clothes:** Dress, Pajamas, T-shirt, Sport Bloomers, Sports Shoes, Pantyhose, Thigh-high Stockings, Sandals, Nurse Uniform, Cravat, Tube Top, Brooch, Ribbon Hair Accessory, Skirt Suit, Nurse's Cap, Sailor School Uniform, Microskirt, Loafers, Lace Lingerie
- **Role:** Step Sister, Student Council President, Senpai, High School Student, Older Sister
- **Subject of:** Pregnancy, Breast Expansion
- **Voiced by:** Shibuya Hime

### Kohinata Umi (小日向 羽美)
A quiet and serious Kouhai who always has a smiling face.
She stands up for the people around her, and always takes that role of a follower.
She is very adaptable and is able to keep up with the protagonist's dirty talk and the bad moods of her classmates.
She lives near the MC and often go to school together, including Miya,
Since she is the youngest of the student council, she is treated like a younger sister, and she sees the protagonist as an interesting senpai.

- **Gender:** Female
- **Measurements:** Height: 152cm, Bust-Waist-Hips: 83-56-85cm, B cup
- **Hair:** Blond, Twin Tails, Long, Straight, V Bangs
- **Body:** Teen, Slim, Pale, Big Breasts
- **Clothes:** School Uniform, Mini-dress, Cloak, Sport Bloomers, Boots, Knee-high Socks, Thigh-high Stockings, Maid's Dress, Court Shoes, Bow Tie, Turtleneck Sweater, Ribbon Tie, Brooch, Rubber Band With Beads, Strapless Leotard, Bunny Dress, Shimapan, Maid's Headdress, Ankle Socks, Torn Pantyhose (damaged), Microskirt, Mary Jane, Blazer, Lace Lingerie, Thong Panties, Fishnet Pantyhose, Strapless Mini-dress
- **Eyes:** Green, Tareme
- **Role:** Student Council Member, Kouhai, High School Student
- **Personality:** Refined, Serious, Watashi
- **Subject of:** Pregnancy, Breast Expansion
- **Engages in:** Bunnygirl Cosplay
- **Voiced by:** Nogami Nana

### Kugayama Natsuki (久我山 奈月)
Miya's classmate and best friend who is always willing to support her. She has a calm personality and always speak politely. She has impeccable grade and is an all-star athlete. Because of her perfection, others tend to keep their distance, and she is friendly and caring to those she breaks the ice with.
She sometimes lecture the protagonist's on the behalf of his step-sister, who cares for him deeply.
At first glance, she seems untouchable, but she has a cute side to her. She's scared of insects and reptiles, and is weak to explicit materials.

- **Gender:** Female
- **Measurements:** Height: 164cm, Bust-Waist-Hips: 91-58-89cm, F cup
- **Hair:** Black, Hime Cut, Long, Straight, Sidehair
- **Body:** Teen, Slim, Pale, Big Breasts
- **Clothes:** School Uniform, Kemonomimi Headband, Necktie, Shirt, Evening Gloves, Gloves, Miniskirt, Sport Bloomers, Knee-high Socks, Pantyhose, Collar, Tank Top, Spats, Sports Swimsuit, Decorative Belt, Torn Pantyhose (damaged), Halterneck Dress, Loafers, Paw Gloves, Blazer, Lace Lingerie, Knee-high Boots, Slit Dress, Thong Panties, Tube Top Bra
- **Personality:** Friendly, Honorable, Relaxed, Refined, Kind, Serious
- **Role:** Senpai, High School Student, Yamato Nadeshiko, Honor Student, Student Council Vice President
- **Subject of:** Pregnancy, Breast Expansion
- **Engages in:** Athletics, Dog Cosplay
- **Eyes:** Pink
- **Voiced by:** Kasuga An

### Makihara Rieko (槙原 理恵子)
The chemistry teacher and the school nurse, as well as the homeroom teacher. She also advises the student council.
She is a suspicious person who seems to have an ulterior motive, and is unable to be read.
Her hobby is to tease the students with her overflowing sexuality, and the MC is often seduced. 
Her deadpan often makes other wonder if she's serious or joking about things.
She is greatly amused by the current situation going on, and is teasing the MC and the girls involved.

- **Gender:** Female
- **Measurements:** Height: 162cm, Bust-Waist-Hips: 93-61-92cm, G cup
- **Hair:** Blond, Long, Wavy, Curtained, Spiky Bangs, Sidehair, Pubic Hair
- **Body:** Slim, Pale, Young-adult, Big Breasts
- **Eyes:** Violet, Hosome
- **Clothes:** Gloves, Miniskirt, Pantyhose, Thigh-high Stockings, Chinese Dress, Collar, Lab Coat, Court Shoes, Peaked Cap, Blouse, Latex, Choker, Sailor School Uniform, Mules, Lace Lingerie, Open Cup Bra, High Heeled Boots, Thong Panties, Latex Thigh-high Boots, Latex Long Gloves, High Heeled Shoes
- **Engages in:** Teasing, Flirting
- **Items:** Whip
- **Subject of:** Pregnancy
- **Role:** Not a Virgin, School Nurse, Sexual Dominant, Homeroom Teacher
- **Personality:** Mysterious
- **Voiced by:** Kawashima Rino

### Tokugawa Takurou (徳川 拓郎)
The serious friend of the MC. He can't leave people in trouble alone, and always tries to help. However, he secretly want the girls surrounding the protagonist.
Because of his position as a student council member, he knows the other heroine to a certain extent and is sympathetic to the MC due to being aware of how bad Miya and Mari are.
He helps the main characters to get to class on time.

- **Gender:** Male
- **Hair:** Blue, Curtained, Short, Parted in Middle
- **Body:** Teen, Pale
- **Clothes:** School Uniform, Glasses
- **Eyes:** Blue, Tsurime
- **Role:** Friend, Classmate, High School Student
- **Personality:** Kind, Serious
- **Engages in:** Not Sexually Involved
- **Voiced by:** Masuoka Yuuji

## Shops
- [Official Website](http://www.bishop.gr.jp/products/ohie/)
- [DLsite](https://www.dlsite.com/pro/work/=/product_id/VJ01006447.html)
- [Getchu](http://www.getchu.com/soft.phtml?id=1106383)

## Releases
### Japanese
- **2010-02-26**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ Limited First Press Ultimate Ero Edition - [Official website](http://www.bishop.gr.jp/products/oh/index.html), [ErogameScape](https://erogamescape.dyndns.org/~ap2/ero/toukei_kaiseki/game.php?game=13248), [Getchu](http://www.getchu.com/soft.phtml?id=670476)
- **2011-02-24**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ DVDPG - [Official website](https://web.archive.org/web/20130207014509/http://www.aicherry.com/aicherryhp/contents/aicherry/jacket/aicdv0266/aicdv0266.html), [Getchu](http://www.getchu.com/soft.phtml?id=698530), [DMM](https://www.dmm.co.jp/mono/anime/-/detail/=/cid=1481aicdv0266/)
- **2011-07-29**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ UMD-PG Edition - [Official website](https://web.archive.org/web/20150416110744/http://www.palacegame.cc/detail.php?id=0039), [DMM](https://www.dmm.co.jp/mono/anime/-/detail/=/cid=h_401plce0039/)
- **2015-06-05**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ Download Edition - [Official website](http://www.bishop.gr.jp/products/oh/index.html), [Digiket](https://www.digiket.com/work/show/_data/ID=ITM0116290/)
- **2015-11-12**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ Renewal Package Edition - DVDPG - [Official website](http://www.aicherry.com/aicherryhp/contents/aicdv0490/aicdv0490.html), [Getchu](http://www.getchu.com/soft.phtml?id=868013)
- **2020-10-30**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ Immoral Edition - Package Edition - [Official website](http://www.bishop.gr.jp/products/ohie/), [ErogameScape](https://erogamescape.dyndns.org/~ap2/ero/toukei_kaiseki/game.php?game=30037), [Getchu](http://www.getchu.com/soft.phtml?id=1106383), [DMM](https://www.dmm.co.jp/mono/pcgame/-/detail/=/cid=648bsp062/), [Toranoana](https://ec.toranoana.shop/tora/ec/item/210006617005/)
- **2020-11-06**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ Immoral Edition - Download Edition - [Official website](http://www.bishop.gr.jp/products/ohie/), [DLsite](https://www.dlsite.com/pro/work/=/product_id/VJ013925.html), [Gyutto](https://gyutto.com/i/item237628), [DL.Getchu](http://dl.getchu.com/i/item4030504), [DMM](https://dlsoft.dmm.co.jp/detail/bishop_0053)
- **2026-06-26**: BISHOP Love Ero Set - [DLsite](https://www.dlsite.com/pro/work/=/product_id/VJ01006447.html)

### English
- **2023-02-19**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ - [Official website](https://sugoivisualnovel.up.railway.app/vns/3496)

### Chinese (simplified)
- **2024-07-26**: Oppai Heart ~Kanojo wa Kedamono Hatsujouki!?~ - [Official website](https://www.eyny.com/forum.php?mod=viewthread&tid=14030020)

## Tags
ADV, High School, Yamato Nadeshiko Heroine, Lesbian Sex, Non-blood-related Brother/Sister Incest, Comedy, Protagonist's Senpai as a Heroine, Male Protagonist, Multiple Endings, Teacher Heroine, Student Council, Nukige, Modern Day Japan, Protagonist's Non-blood-related Sister as a Heroine, Map Movement, High Sexual Content, Group Sex of One Male and Several Females, Student Heroine, Pregnant Sex, Sex Under the Necessity, Under the Same Roof, Harem Ending, Heroine with Zettai Ryouiki, Heroine with Sexual Experience, Adult Heroine, Sex Involving Drugs, Tomboy Heroine, Big Breast Sizes Heroine, Protagonist's Kouhai as a Heroine, Energetic Heroine, Urination Fetish, Female Domination, Vibrators, Defloration, Sex in Public Places, Anal Penetration, Footjob, Boobjob, Cheerleader Heroine, Cosplay, Heroine with Swimsuits, Heroine with Tights, Missionary Position, Sixty-nine, Super Deformed CGs, Sounds of Copulation, Blowjob, Handjob, Student Council President Heroine, Impregnation, Lactation During Sex, Date Display, Heroine with Sport Bloomers, Intercrural Sex, Bukkake, Anilingus, Masturbation, Breast Expansion, BDSM, Cunnilingus, Student Council Member Heroine, Student Club Member Heroine, Balls Sucking, Inflation, Brocon Heroine, Doggy Style, Female Ejaculation, Ejaculation Choice, Outdoor Sex, Clothing Damage, School Nurse Heroine, Petplay, Fingering, Excessive Semen, Cowgirl, Reverse Cowgirl, Sex in Water, Tsukkomi Protagonist, Changeable Clothes, Standing Sex, Sitting Sex, Spoons, Butterfly, Piledriver, Ahegao, Bathroom Sex, Mutual Masturbation, Mischievous Heroine, Soapy Massage, Kissing Scene, Background Moans, Twin Boobjob, Facesitting, Reverse Missionary, Quickie Fix Position, Shoejob, Sex at School, Blowjob Duck Face, Tribadism on Penis, Masturbation with Object, Anal Fingering, French Kiss, Pantyjob, Breast Smothering, Music Recollection, Adult Breast Sucking, Manual Prostate Stimulation, Dog Cosplay, Heroine with Latex, Bunnygirl Cosplay, Threesome, Sex on a Roof, Sexual Cosplay, Anal Gaping, Pissing on Others, Pregnancy Good Ending, Single Boobjob, Single Footjob, Single Handjob, Single Buttjob, Single Blowjob, Vaginal Masturbation, Pissing, Vaginal Fingering, High School Student Heroine, Sex with Protagonist Only, Heroine with Big Breasts

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---
*View the full details at [pinovel.net/v3496](https://pinovel.net/v3496).*

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```