Oppai Igai ga Dame Sugiru Ane


TitleOppai Igai ga Dame Sugiru Ane
Original titleおっぱい以外がダメすぎる姉
LengthMedium (10 - 30 hours)
PublishersMarine & Lune
Shops» JP¥ 3561 @ DLsite (jpn)
» JP¥ 6600 @ DLsite (jpn) (bundle)


Although the protagonist doesn't have any special characteristics, his skill in home economics only, is very high. To say nothing of just cooking, his skill in doing all the household chores is unimaginable for a student. Rumor of him being a skilled housewife was spread from his friends from class. The reason for protagonist becoming like this was due to the 3 hopeless sisters who lived with him.

The eldest daughter, Kanako is the homeroom teacher of the protagonist. She is adored by her students as well. However, inside the home, she lives with a sloppy figure with only wearing underwear. Not only cooking, but is hopeless with every household chores.

The second daughter, Yume who is a neat and clean, kind nurse who is heavily relied upon by the patients and doctors alike in the hospital. Loves to drink alcohol. After getting drunk, approaches her younger brother in an indecent manner, taking her clothes off.

The third daughter, Hinori who is the student council president. An intellectual student who has top grades and has lots of trust from her teachers. However in reality, is a very jealous person and becomes sullen if she doesn't get attention from her brother.

With such bad sisters, a new problem happened during this spring.

The sisters contracted a disease "Cleopatra Syndrome" which involves a love addiction and heavy dependence on their younger brother. The protagonist was told from the doctor that the only cure to this illness is "younger brother's sperm". "Can you do such things with your sister...?", while the protagonist being bewildered with thoughts like these, the 3 sisters started approaching him to take advantage of this situation.

However, because of exceeding the limits of his body due to excessive self indulgence in addition to his normal life, the brother started resisting. Therefore, his sister made a proposal "You can take advantage of our breasts as much as you like."

Relieving the stress accumulated from his sisters every day... Above all, being charmed by the benefit of being able to do as much as he pleases to the huge breasts of his sisters, which they show in the every day life, the protagonist accepted the proposal.

But that was a strategy made by the sisters to cross the line with the brother, they liked very much!

And the curtain opens with the flirting and erotic happenings of the younger brother who is being manipulated by his no-good sisters---

[Translated from website]

Hide spoilersShow minor spoilers | Show sexual traits


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Amakami Kotarou天神 虎太朗
MeasurementsHeight: 170cm
RoleHigh School Student, Younger Brother
Engages inPolygamy


In the lower region in terms of results, exercise and even appearance. An existence that doesn't stand out too much.

However, the results in home economics and after-school cleaning are different. He has ability of surpassing even his teacher in terms of cooking; during the time of cleaning, shows ability of working quicker and more refined than even maids. His skill in domestic chores, is unimaginable for a student. Rumour of him being a skilled housewife is spread from his friends from class.

All of this skill was gained due to taking care of his sisters. The person himself is not very pleased with it.

However, has curiosity towards lewd things as expected of a man, his age. While he was worried about his defenceless sisters, his inner feelings were of a keen interest in offering his sperm to them.

While having a feeling of immorality, will he himself become aggressive...!?

[Translated from website]

Main characters

Amakami Hinori天神 妃乃里
MeasurementsHeight: 165cm, Bust-Waist-Hips: 92-??-??cm, E cup
HairBlack, Blunt Bangs, Hime Cut, Long, Sidehair, Straight
EyesTsurime, Violet
BodyAverage Height, Pale, Slim, Teen
ClothesBlouse, Bra, Dress, Naked Apron, Pajamas, School Uniform
PersonalityBrocon, Jealous
RoleHigh School Student, Older Sister, Student Council President
Subject ofPregnancy
Voiced byTachibana Mao


The youngest of the 3 sisters. She is a talented student who works as the student council president and always stays at the top in grades.

The eyes gives off an impression of being sharp and cool. Sense of responsibility is strong and hates bending of rules. She doesn't forgive either students or teachers for this. Even takes a step back inside the school even for her beloved younger brother. Always takes a strict attitude towards him.

However originally, since she was a spoilt child, wants her brother to give her attention.

After coming home and becoming alone in her room, spends time flirting with a stuffed doll named after her brother. When not getting attention from him, in displeasure, she takes out her frustration on the stuffed doll.

Also, she seems to like the smell of her brother. Sometimes, she is seen as sniffing her brother's t-shirt in the bathroom.

She pays attention to her brother often but then denies this observation by saying "This is different.".

[Translated from website]

Amakami Kanako天神 翔奈子
MeasurementsHeight: 172cm, Bust-Waist-Hips: 98-??-??cm, G cup
HairBlue, Bun, Intake, Sidehair, Straight, Waist Length+
EyesBlue, Hosome
BodyAdult, Average Height, Pale, Slim
ClothesBlouse, Bra, School Uniform, Shirt, Skirt Suit, Sports Uniform, Trousers
PersonalityBrocon, Deredere, Lazy, Outgoing
RoleOlder Sister, Teacher
Subject ofPregnancy
Voiced bySatou Haruka


The eldest of the 3 sisters. Homeroom teacher of the protagonist.

Has a frank personality but is relied and supported by her co-workers and students.

However, has an opposite impression in her younger brother's mind. After coming home, loiters around wearing only a shirt and a piece of underwear. Cleaning, laundry and even preparations of making food, everything is left for her brother to do.

She is number 1 in popularity inside the school because of her appearance and personality. But she has no interest in any other man except her brother.

Teases the protagonist even inside the school. When catches the sight of him, tries to casually touch him or begins sexually harassing him. Other guys shows signs of jealousy but the protagonist himself feels very embarrassed and perplexed.

[Translated from website]

Amakami Yume天神 柚女
MeasurementsHeight: 161cm, Bust-Waist-Hips: 105-??-??cm, H cup
HairPink, Ponytail, Sidehair, Straight, Tiny Braid, Waist Length+
EyesCyan, Tareme
BodyAdult, Average Height, Pale, Slim
ClothesBaby-doll, Bra, Chinese Dress, Miko's Dress, Naked Apron, Nurse's Cap, Nurse Uniform, Towel
PersonalityBrocon, Kind
RoleNurse, Older Sister
Engages inDrinking
Subject ofPregnancy
Voiced byMisonoo Mei


The second among the 3 sisters. A nurse, who works in the hospital next to the school.

Although has a very gentle and cheerful personality, when it comes to taking care of patients, is very earnest. Knowledge regarding nursing is also very deep.

However, on the other hand, is a very heavy drinker to the point, that she says that she will die if she cannot drink alcohol every day. She wants to drink while watching her younger brother. She never drinks, if not in front of her brother.

Although becomes pessimistic while drinking, her aggressiveness towards her brother increases. Starts approaching him while taking off her clothes.

One time when her brother got angry, started taking clothes off, while crying.

Even after waking up from her drunk state, remembers "I will take responsibility" and so approaches her brother again.

[Translated from website]