Manga Review: Boku wa Mari no Naka (Inside Mari)

Shūzō Oshimi's Boku wa Mari no Naka
Shūzō Oshimi’s Boku wa Mari no Naka

From the same author as the soul-searching series Aku no Hana, Shūzō Oshimi takes us on another exploration of the darkest niches of the human psyche in Boku wa Mari no Naka. The story as is almost ubiquitous of Oshimi’s style of writing revolves around a very select few characters but we get to get to know them well. Very well. Maybe too well. If you’re searching for a too long; didn’t read: I can recommend this series but with a caveat: it’s not for everyone. The art is splendid, the character development is splendid, the plot twists are interesting (although I did guess the ending correctly) but the substance of the plot itself, along with some explicitly mature themes, means you might be put off. If you like a dive in the deep end of the raw psychological struggles and confrontations some young people face however, this will be to your likening.

You can read anything in blue safely, however anything in black may be/is packed with spoilers.

The Story

The story initially follows a beautiful high school girl called Mari Yoshizaki and a “hikikomori” (socially alienated person) called Isao Komori. Isao lives in seclusion, spending his days playing video games and watching pornography. His only daily highlight is seeing Mari every night at a local convenience store. The story begins in earnest when one day Mari wakes up and immediately realizes something is wrong with her body. Or better, Isao wakes up realizes he is Mari.

This synopsis does absolute zero justice to the story! Saying much more though would be a spoiler. Suffice to say that this is no ordinary gender bender flick. 

Isao wakes up as Mari and panic ensues. Where is he? Who is he? How is this possible? From the get-go you notice that this is indeed not an ordinary gender bender series which generally exemplify the hilarity of the very idea. Not so in Boku wa Mari no Naka. Waking up as someone else, if it ever happened to you for real, must be a terrifying and extremely confusing experience.

Over the course of the story we see Isao trying to adapt to his apparently new lifestyle. He has no idea how it happened or how to reverse it, so he has no choice but to take on the role of Mari. This brings a number of social but also very practical difficulties. Not only does he have to find ways to actually act as a girl, he has to make sure he also acts like Mari specifically. On top of that he’s treated to some of the disadvantages of being of the female gender. All of this, Oshimi manages to portray vividly and very realistically. There is no hilarity to this situation. Isao is truly distraught and is trying to cope with every day life.

Eventually he’s found out, by another highschooler who appears to know Mari much better than anyone else. She, Yori Kakiguchi, quickly discerns that something is wrong with the “Mari” she knows and comes to the conclusion that Mari is not Mari. When confronted by this, Isao confesses his predicament. Together they then try to solve the mystery behind the disappearance of the true Mari. This doesn’t go without trouble as Yori absolutely loathes the real Isao and finds the thought of him inhabiting Mari’s body more than utterly repulsive.

As the story progresses, Isao gets to know more and more about the “real” Mari. Not just the idealized image of her he had. These revelations, including the fact that the “real” Isao is also still there, in his apartment playing video games and being generally useless, gradually put the pieces of the puzzle together. The story shows us the image each of the characters has of the other characters and then they’re forced to get to know one another extremely intimately.

Like this Boku wa Mari no Naka manages to show us just how the image we have of a person can differ from how they really are. The perfect angel-like Mari who is popular and has good grades is the image Isao has of her. This perfect image is slowly deconstructed as he learns how the real Mari is; full of shortcomings and anxieties just like any other real person.

What I like about this plot is that it avoids many of the typical cliches so ingrained in Manga culture. Yes the circumstances appear supernatural but really we’re following the struggles of ordinary people cast into emotional depths from where they’re trying to climb out. None of them are perfect and they will at times act illogical or counter-productively. The characters undergo a number of changes to their determinations and ambitions; sometimes falling to cynicism and just giving up and at other times scrambling themselves together. Kind of how real people like you and I would act when faced with life’s difficulties.

There are some mature themes and scenes in Boku wa Mari no Naka. Oshimi’s story follows three characters very intimately and doesn’t shun portraying the privately intimate parts in his story. At one point Mari (Isao) has her period and as Isao is completely taken by surprise by this (because duh) and we do get to see the aftermath up close of this. Mari is also drawn naked and at first Isao is rather uncomfortable with this himself. But as time goes on it just becomes a routine to him, and even we the readers become accustomed to just seeing Mari’s body as something completely ordinary. I mean, we see ourselves naked pretty much daily right? Oshimi manages to capture this brilliantly. There are also some sexual acts which are portrayed very vividly and realistically. Oshimi has ignored the fact that Japan has censorship laws altogether with these for the most part. All of the aforementioned mature themes are perfectly justified and have an integral place in the story. But if you’re especially wimpy or feel a need to preserve your pristine innocence, be warned.

Around 90% into the story, just before the mystery is starting to unravel, I guessed the ending. I won’t tell you literally but Oshimi managed to write a story which is a gender bender and explain it perfectly and with such plausibility that it could be reality. That alone is such an amazing feat that it tells you how solid the plot is, especially since it all makes perfect sense at the very end. Truly, Oshimi has perfected his story telling skills since Aku no Hana. Boku wa Mari no Naka will leave you contemplating about the many masks we wear in social life and will make you wonder how the people you’ve idolized and loathed really are underneath their own masks.


The story follows three persons of particular interest. There are some side-characters but they play exceedingly minor roles, or are just there to provide some context. It’s really these three people the story explicitly and intrinsically revolves around. Having a very limited cast is a matter of preference. Some series have hosts and hosts of characters and, not surprisingly, fail to develop any of them very thoroughly (sometimes not even the main protagonist). With just three main characters this won’t be the case.

Isao Komori Boku wa Mari no Naka (Inside Mari) Isao Komori A young adult and high school dropout who spends his days playing video games and watching porn. He lives by himself in a small apartment as a “hikikomori”, which is a person who’s alienated themselves from society due to failing at their professional life (e.g. dropping out of school or not finding a job). His only daily highlight is seeing Mari Yoshizaki at the local convenience store every night. Isao is infatuated by Mari and idolizes her as a perfect “angel” because of her beauty and apparent success in school and social life.
Mari Yoshizaki Boku wa Mari no Naka (Inside Mari) Mari Yoshizaki A young woman who attends high school. She has good grades and is popular among her peers. She lives in a nice house with seemingly supporting parents. Mari is “stalked” by Isao every night as she visits a convenience store but seems oblivious to this fact. Mari however has her own secrets, which are a far cry from the pristine appearance she puts up.
Yori Kakiguchi Boku wa Mari no Naka (Inside Mari) Yori Kakiguchi Fellow attendant of the high school as Mari Yoshizaki. Yori seems to be a more average student but, like Isao, is infatuated by Mari.


It is exceedingly difficult to pinpoint the protagonist in Boku wa Mari no Naka. You’d think it’s Isao but in the end we find out he’s really not. In fact he’s what we call a “symbol” to the protagonist. A symbolic character is one against which the protagonist mirrors themselves, either positively or negatively. However for this to be true Mari would need to be the protagonist. But she lacks all the traits of one. The character of Mari is only briefly shown in the beginning and revealed to us in the very end due to the body possession. This only leaves Yori to consider and she does have the most protagonist traits of all three; she’s a main character, she’s trying to do the right thing, she’s overcoming the hardships presented by the plot, and so on. This is something neither of the other two are actually very concerned with.

In the end I must conclude that Boku wa Mari no Naka has no protagonists. Life threw these characters melons and they dealt with it for better or for worse. They didn’t rise to the occasion like some hero or do anything we’d expect of a story’s typical protagonist; they acted as people. Don’t get me wrong, there’s nothing boring about this. In fact it makes it that we can relate to the characters very easily, much more so than with a person who we know possesses some kind of supernatural ability. In the end we know their supernatural ability will be used as a plot device to further the story. We cannot possibly know how Mari, Isao or Yori will cope or react since the author didn’t give them such a plot device. This is what makes Boku wa Mari no Naka, and other stories deeply rooted in realism, actually more suspenseful and thrilling to read in many ways.

Each of the three main characters is an integral part of the puzzle. The three combine into a full story. Leave out any one of them and you end up with a story which will never see completion. They’re the bare minimal, yet perfectly sufficient amount of characters, and being given character development to form a complete story. Boku wa Mari no Naka is about learning who these people really are, and interestingly for each of the Characters to get to know each other. Doing so is one and the same as completing the plot of the story.


As in Aku no Hana, Oshimi makes use of line arts which are frequently heavily shaded. This makes the artwork in Boku wa Mari no Naka less crisp but gives it more depth (as opposed to not shaded but very crisp). Oshimi’s feel for proportions and geometry is startling and I can’t reveal any artistic mistake (although I’m no expert mind you).

Inside Mari Line Arts
Line arts accentuated by heavy shading in a closeup panel.


It is nothing spectacular or special, however, and I’ve seen more impressive artwork in similar genres (Oyasumi PunPun for instance). That’s not to say Boku wa Mari no Naka has sub-par artwork. On the contrary, it’s quite good. Especially when it comes to portraying emotions Oshimi’s work shines.

Inside Mari Line Arts
Tears of happiness. Most convincing.


As a story set in the real world you’ll find no weird proportions to people and Oshimi even made efforts to make his characters look “ordinary”, in other words not perfect or idealized. Overall the artwork is very neat and well taken care off. Characters stand out and the geometry and surroundings are easy to recognize and view.

Notable and unique Aspects

What stands out the most in Boku wa Mari no Naka is really how well Oshimi understands the human psyche. He uses this both to construct his characters as well as goad and lead on his readers. Japanese philosophy deals a lot with the “human condition” and Oshimi is an expert in the field. Not heavyhearted or overly dramatic but in a way we can instantly relate to.

What further stands out is the raw realism of the story and the artwork. Oshimi doesn’t leave out anything from the lives of the characters and while doing so, doesn’t care a wooden nickle about what Japan’s censorship laws say. It may sound odd but this comes to expression best by the depiction of pubic hair. Wildly controversial in Manga and all but nonexistent in Anime as well as usually just censored away in the first place; Oshimi simply depicts his characters as they really are. Human. 


Coming to the closing arguments of this review, I can do nothing but highly recommend Boku wa Mari no Naka to any avid Seinen reader who isn’t looking for Ecchi. The plot is one which deeply involves you in the lives of the three main characters. The characters themselves are easy to relate too and undergo a lot of development throughout the story. They are unique yet innately human. They could literally be you or me. Despite being technically a gender-bender story, it lacks any of the cliches those kind of stories usually have. Instead Oshimi takes us on a tour of the human psyche, one which is in distress.

The plot’s length is exactly right, it’s not milked to death yet not too short to leave plot holes or things to be desired for. Oshimi’s very unique take on character archetypes, character development and story progression will keep you interested. Of course, the (very) mature themes might not be suitable for everyone but they do have a very natural and justified place in the story.

Boku wa Mari no Naka will leave you contemplating on the big masquerade which we’re all a part off.

Leave a Reply