ONIMAI: I’m Now Your Sister! – Episode 1

By: Cy Catwell January 5, 20230 Comments
Mahiro goes to get sized for a bra.

Content Warnings: Forced feminization, sexualization of a sibling, underage nudity, fan service

What’s it about? Oyama Mahiro was your everyday, eroge-loving dude. That is, until their mad-scientist sister, Mihari, experimented on them and they woke up as a woman, which–as far as Mahiro is considered–is a life-changing, disastrous outcome. However, little sister Mihari is determined to turn this into a net positive for them both by using this opportunity to help Mahiro grow from NEET to NEAT FREAK…if they can figure out this whole gender thing.


Let me say this up front: there’s four good things about this show.

  1. The potential for a trans reading
  2. The art style
  3. Bottomsley and Toppington
  4. The background music (really, the music overall)

Other than that, ONIMAI: I’m Now Your Sister! (hereafter ONIMAI) goes for the lowest, grossest, horniest jokes possible. Honestly, we should be grateful that it didn’t get actual horny because something tells me this show would have these siblings fuck if it could be plot relevant to Mahiro learning how to live with a vulva and breasts, both of which the show will never let you forget about.

For the sake of this review, I’ll be referring to our protagonist Mahiro as they/them. I made this choice because Mahiro never uses a specific gendered pronoun, but also, the show doesn’t necessarily gender them as female either. Rather, it presents them as a girl while refering to Mahiro with masculine language. For example, Mahiro’s sister Miharu calls them “onii-chan” even when Mahiro looks and presents with a cis female body, though I also think there’s more value in reading this as a trans feminine body with a vulva than moving from one binary to another. Miharu also uses “he” and “his” when refering to Mahiro, and Mahiro also uses “boku”, which is typically a masculine pronoun but also has been used by cis gender women in media as well. Because of this, and because of my ethics here at AniFem, they/them feels like the most respectful way to talk about Mahiro’s presence in this show and to speak to our readership as well.

Mahiro realizes that their body works a bit differently now.

Episode 1, “Mahiro’s Confusing New Body,” asks the question, “How depraved do you think a Crunchyroll anime can be?” and answers it by giving us all manner of weird horny situations, ranging from copious shots of underage butts to finding out Mahiro’s sister tracks them via cameras to a “check up” to the most overt sibling flirtation possible. It truly is a roller coaster of emotions, all of them making me go, “Ew.”

And like, ONIMAI has a solid two minutes of good stuff right up front before the lead drops their pants and their sibling reveals that they experimented on them, reducing them from a shut-in NEET to a middle schooler that looks like they’re ten. It only continues to decay from there, especially when Mahiru’s sister Mihari informs them of the vaginal (the show says female) orgasm and how it’s 100 times more powerful than a penile orgasm. 

And don’t get me started on the opening: there’s so many teenage butts that I shouted, “The FBI’s going to come get me just for reviewing this anime!” because it’s just that blatant and discomforting. The song is a banger but like…at what cost?!

But more specific to the plot, the premiere is about Mahiro adjusting to a new body, a plot that in a very different show, might have been funny because bodies are weird and gender is a joke. Instead, epiosde one spends most of its time having Miharu be a little too eager to see their sibling’s borderline prepubescent body while completely ignoring Mahiro’s on-going dissociating and dysphoria from the situation they’ve been unceremoniously thrust into. 

There’s some comedic beats, like Mahiro realizing they need to sit down to urinate; and there’s even some touching moments, like Mahiro realizing they like feminine clothing. But all of that is parallel with viewers having to dodge shots of Mahiro’s feminized body and talk of masturbation to actually enjoy those crumbs of good plot.

Mahiro wakes up to realize that their body isn't quite what they expected.

There’s no avoiding it: Onimai is fucking disgusting. I watched it three times and I stand by that: it made me intensely uncomfortable. It’s a really, really gross show, and that’s just flat-out a shame because there’s so many moments where it’s not discomforting. Please, Studio Bind, I’m begging you: stop using your amazing skills to do anime crimes.

Granted, I don’t know why I didn’t expect to have my eyeballs seared by this show seeing as Studio Bind also produced Mushoku Tensei, a series that is skin-crawling in concept and pretty in aesthetics, but like… Onimai feels like some kind of new low. Its benign art style really undercuts how utterly voyeuristic this premiere is, and really sugarcoats one of the most uncomfortable plots I’ve encountered since Oreimo, and that’s saying a lot because that series is fiercely horny. ONIMAI is “Chris Hansen’s To Catch a Predator” levels of icky with how it centers Mahiro’s body not as a body in transition but instead, a sight gag. It all comes down to the camera and the voice acting direction, which really adds about a hundred moans and whimpers to scenes where Mahiro is having some sort of strange, erogenous experience.

It is uncomfortable from 00:00 to 23:40, and no amount of pretty animation is going to make me like this, even though Onimai is really aesthetically beautiful with a soundtrack that I genuinely would like to have a physical copy of. There’s so much good in the anime soup here: that is, until someone decided to up the ante on the source material and make it have a certain kind of “audience appeal” that still has me baffled.

What’s really strange is that the in some senses the fan service is rather tame. Yes, there’s a lot of butts and crotch shots and nudity, but it’s…dare I say, it’s actually quite tame compared to more overt fetish shows. Which I am immensely thankful for, because there is a scene of Mahiro needing to use the bathroom and I was nearly 100% sure we’d have a scene of them trying to navigate urinating into an empty tea bottle with a vulva. Nobody wants that.

Mahiro tries on their first article fof eminine clothing.

I’m not a woman: at least, not anymore. I haven’t really been one in about a decade, and over the course of last year, came to realize I was trans masc and agender. That said, I am trans and I was raised as a Black, AFAB person, so when I say this show made me uncomfortable about my body from a feminine context, I mean it. I might not be a trans woman or trans feminine, but I understand the leering all too well, and this show doesn’t show any kind of consideration towards how upsetting that actually is.

It really is a shame that Onimai ended up this way because it’s a really curious trans narrative–in theory. I firmly believe that without the gross elements, this could be a show about two siblings figuring out gender and transition together with what’ll eventually amount to a gaggle of female friends. I’d love a show with this level of production telling a comedy slice-of-life story about two siblings navigating a sudden gender change.

Instead, we get mad-scientist Miharu peeping her sibling’s bod and experimenting on them for “the greater good”; we get Mahiro attempting to turn No-Nut November into an entire lifestyle because of the jarring dissonance with their genitalia and gender identity. The former can’t be saved, but the latter could have been rewritten and positioned, in a better show, to be a moment where someone who’s literally not related to Mahiro steps in and helps them understand how their sexuality and identity might be changing.

However, since said transition is predicated on Miharu experimenting on Mahiro in the first place, all hope for a plot that isn’t fraught immediately goes out the window. Doesn’t matter that Miharu is doing this for Mahiro’s own good: the base for Mahiro’s forced feminization is a plot gag that leaves a wicked bad taste in my mouth and worse, heavily fetishizes Miharu’s (and the show’s) gross obsession over their sibling’s underaged genitalia, nipples, and chest. 

Mahiro goes to get sized for a bra.

Now, there’s a long history of forced feminization as an outlet for people: there’s a lot of power in it, and it’s helped a lot of trans feminine folks crack their egg. I can’t personally speak to any experience with that because for me, being forcible feminized occurred in being assigned AFAB, not in discovering gender as a freeing experience from a feminine perspective. I think that’s what bothers me most here: the anime takes away a lot of the potential for enjoyment for Mahiro’s initial experiences as a woman/young girl. There’s definitely moments of that: anytime Mahiro gets to do something affirming, there’s this charming, sheepish smile they get. But then the show seems to almost readily ruin it, which is something I hope lessens not only for the general audience watching this, but for fans who are coming to this show specifically from the manga, which seems to have been the impetus for cracking a lot of people’s egg.

I think there should be room for transness and queerness to be messy and gross: I think there should be room for gender to be gross and icky in a fun, sexy, sensual way. I actually think that’s quite necessary, as often, queerness and transness get put on pedestals, but like, real talk? I want weird stuff in my queerness and transness. I want to capture the entire breadth of experiences because purity culture sucks and queerness of all flavors has always been weird.

However. ONIMAI isn’t that.

This show is so far from being an actual trans narrative, despite the potential for it with the nature of its protagonist. At least that’s the case with the anime: I can’t accurately speak to the manga as I haven’t read it and, truth be told, have been fiercely put off from reading it after watching this premiere. Maybe one day I’ll circle around to it, but for now, it’s a nope from me, dawg. And while I’m sure that this show will find its audience, I think I’ll always lament that this show took to using its youthful-looking protagonist as a plot gag rather than actually going for something that might be genuinely “wholesome”, to use a rather fraught word. The way ONIMAI is right now feels like a show made by cis people for cis people, and for me, does a disservice to its trans (fem, specifically) audience: I don’t feel like this is a series made for me as a trans individual.

I just feel like my body is some sort of comedic punchline.

About the Author : Cy Catwell

Cy Catwell is a Queer Blerd journalist and JP-EN translation & localization editor with a passion for idols, citypop, visual novels, and the iyashikei/healing anime genre.

You can follow their work as a professional Blerd at Backlit Pixels, get snapshots of their out of office life on Instagram at @pixelatedrhapsody, and follow them on their Twitter at @pixelatedlenses.

Read more articles from Cy Catwell

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