Oniichan wa Oshimai!

Self-professed "home security guard" Mahiro Oyama has not left his home in years, secluding himself in his room playing erotic visual novels. This depraved lifestyle causes his prodigious sister, Mihari, to worry about his well-being. In hopes of solving this problem, she devises a plan to rehabilitate him back to normalcy.

The first part of Mihari's plan is to concoct a medicine that changes her brother's biological constitution into a bona fide female, much to Mahiro's vehement dismay. Stuck in this predicament, Mahiro has no choice but to live out his life as a cute girl until the effect wears off—if it ever does.

[Written by MAL Rewrite]

Oyama, Mahiro Main

Kouno, Marika Japanese

Oyama, Mihari Main

Ishihara, Kaori Japanese

Hozuki, Kaede Supporting

Kanemoto, Hisako Japanese

Ouka, Asahi Supporting

Yuuki, Kana Japanese

Hozuki, Momiji Supporting

Tsuda, Minami Japanese

Murosaki, Miyo Supporting

Hioka, Natsumi Japanese

Fujimi, Nemu Supporting

Sakurai, Mia Japanese

Leonardo Supporting

Uchida, Yuuya Japanese

Nagase, Miyako Supporting

Oda, Karin Japanese

Kitahara, Yuriko Supporting

Nagae, Rika Japanese

Ootomo, Toshiya Producer

Hatakeyama, Takurou Producer

Hishiyama, Mitsuteru Producer

Higashi, Mao Assistant Producer

Reviews

Jan 4, 2025

S1L3NT-L0V3RS

Recommended

[7/10] Good.

Contains some minor spoilers, but nothing big, don’t worry ;)

I guess we all know why I watched it ? If u don’t, easy answer : Studio Bind. At this point, Studio Bind’s just flexing their animation and I love it ! Even their ED animation has more budget than some whole others shows. This show is just a pure beauty visually! With this kind of animation n quality, I usually give 10 easily.. Now, what’s the problem ? It’s the fact that Fan-service has to be present in every episode, like whyyy, the OP’s just disgustingly filled with this type of bullsh’t. I don’t ... mind some fan-service, ecchiness or anything, some of it is fine, but why overuse. Without mentioning, they’re « smol » :( won’t say that every person who enjoyed the protagonist’s fan-service r lolicons n pedophiles but yh.

Plot - It’s a pretty original story. The protagonist, Mahiro, who hasn’t got out for 2 years is changed into a girl by his little sister, Mihari, for some amount of time. Their parents chose some original names, right ? I thought, I would just hate the gender change theme, but it was so well done, I loved the show! So Mihari lives their life as a young woman.. n they get in some rlly funny scenes, honestly, I laughed a lot at some points. Mihari’s mission is to get her brother back, getting out of his room, his video-games n get closer to her again. I really enjoyed the last part I mention, their relationship was so cuteee. The whole show is cuteee honestly ! Mahiro met their sister’s bestfriend Kaede, a sweet character, but I didn’t like her look, the usual « sexy character with a VeRy big chest » which is completely avoidable.. but anyways I loved her character! At some point of the show, Mahiro has to go back to school, this is when this show gets weirder.. uhhh.. girls relationship, bath scenes, more bath scenes, n more bath scenes, thermal source scene.. lemme mention that Mahiro’s classmates are 12 :D 2 of them are literally flat-chested pre-pubescent girls, just disgusting :( without mentioning the whole lot of garbage innuendos, like whyyy do you need this, just triggering. But this show has a lot of funny scenes, n many cute ones! So pretty balanced.

Animation - flawless, just splendid.

Characters development - Great. That’s it. I just loved every single character n we get a glimpse of everyone.

Soundwise - Overall it was great. OP n ED were wonderful, if u don’t pay attention to the fan-service, the visual’s just amazing n the sound’s catchy, loved them.

Designs - Sumptuous, just magnificent.

Plot - 9/10
Music - 8.5/10
Visual - 10/10
Character development - 9/10
Story telling - 8/10

This show needs a second season, as Mahiro’s school isn’t finished yet. We need to know how they manage to leave all her friends knowing the fact that no one apart from them, know about this gender change. Most importantly, we need to see more of their relationship cuz they’re just so cuteee, just loved the ep when Mihari’s sick! One of my fav watch of the year!

Looking forward to the next shows by Studio Bind this year. Normally we’re getting at least 3 more shows by them this year, quite excited to watch!

Will definitely recommend you this great anime ! But avoid if u have some issues with small characters’ fan-service. Overall it ended up with a « good » rating cuz of the disgusting parts mentioned above. One of those shows that you just loved but that you can’t recommend to some close friends cuz of their fan-services. Anyways, a good show to watch! Enjoyed throughout the whole watch.

[7/10]

Reviewer’s Rating: 7

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Dec 18, 2024

useless-cheese

Mixed Feelings

This Series does not adapt all the chapters and it adapts them in an odd order. This anime is fun and good but like horimiya just read the manga and get a fuller picture.

if you see this review after wards you only missed chapter 4(very trans), 19, and 23, along with most bonus chapters/pages

The anime itself is still good, with a bubbly art style that makes our cast look good. the humor in this is good for an anime but what makes this series any fun is watching the characters interact. The main cast are all so charming and distinct.

Reviewer’s Rating: 7

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Dec 11, 2023

Smilomaniac

Not Recommended

The premise is from the get-go that a man (older brother, true gamer nerd/enthusiast, recluse but ultimately harmless) wakes up having been turned into what looks like a pre-teen girl by his "mad scientist" sister, via a drug. In her room she has a manual on her desk which deetails how she wants to turn him into her little sister, meaning this is entirely deliberate with an agenda.

It SOUNDS like this should be a hilarious comedy to give a guy what he deserves in order to appreciate what being a girl or a woman is like, as punishment.
That's not at all what it is. ... This is entirely about a selfish wish from the sister's side to get rid of her nerd brother and gain a cute little sister that she can dress up and take care of and the brother-turned-sister just goes along with it for no good reason with no strong opinions one way or the other.

It's dressed up as being wholesome and shows some awkward situations because it's a gender-bender, but really it just seems like a small girl's coming of age slice of life with questionable fan service. Gotta ask, why isn't that just the story?

So you're left wondering where the plot is going and why you're looking at pre-teen panty shots. Where's the joke?
If you think about the premise a little, this is a creepy story about a woman who abuses her sibling and psychologically manipulates them, besides the fact that she drugged him with what seems like permanent side effects.
Again, this could've been interesting, she could've been a genuine psychopath who mentally tortures her brother, but instead it's played off completely straight and even lovingly.

Moral of the story? It's better to be forcefully gender transitioned and socially groomed than be a male recluse.

You tell me how this isn't wildly thoughtless and even offensive.

I'd like to touch on another thing which is the topic of being transgender in the 2020's.
How odd and insensitive it must be to watch someone with no interest in becoming the opposite sex just get a pill or some liquid and magically transform with no effort, no pain or any cost.
I'm not an "ally", I don't particularly think encouraging being trans is at all healthy or the right thing to do, but I can't help but feel that this show has to just twist the knife for a person who wants to be the opposite sex and feels genuine grief with who they are.

It's not the show-maker's responsibility for how it makes people feel, but I think it's another thoughtless and irresponsible way of approaching what could've been a good and interesting story.

It's not impossible to view past its flaws and just enjoy a 'wholesome' story with a bit of ecchi, but man... this is in poor taste.

Reviewer’s Rating: 4

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	Poll: Oniichan wa Oshimai! Episode 2 Discussion ( 1 2 3 4 ) Stark700 - Jan 12, 2023	198 replies	by Cooomer »» Jan 5, 10:30 AM
	Poll: Oniichan wa Oshimai! Episode 12 Discussion ( 1 2 3 4 5 ... Last Page ) Stark700 - Mar 23, 2023	252 replies	by Hikkicomoreye »» Jan 4, 8:04 PM
	Poll: Oniichan wa Oshimai! Episode 1 Discussion ( 1 2 3 4 5 ... Last Page ) KANLen09 - Dec 24, 2022	335 replies	by Cooomer »» Jan 3, 3:09 PM
	Poll: Oniichan wa Oshimai! Episode 11 Discussion ( 1 2 ) Stark700 - Mar 16, 2023	61 replies	by HiljainenSipuli »» Jan 3, 2:44 PM
	Poll: Oniichan wa Oshimai! Episode 9 Discussion ( 1 2 3 ) Stark700 - Mar 2, 2023	107 replies	by tery1 »» Nov 21, 2024 8:20 AM