Yuuri Shibuya was living a pretty normal life. That changed the day he was dunked into a toilet after an attempt to save a classmate from a gang of bullies. Instead of just getting a good soaking, he's pulled in. The next thing he knows, he's in a world that vaguely resembles medieval Europe. If that's not odd enough, he's told that he is to be the next Maou (Demon King), just because he has black hair and black eyes.
The Maou is the King of the Mazoku (Demon tribe), who are coexisting not-so-peacefully with the humans in this world. Much to his subjects' dismay, he's totally different from the rulers they're accustomed to. He's kind, considerate, a believer in justice, and not willing to use violence to solve conflicts. Not exactly someone they want running a country on the very brink of war. Now, Yuuri has to deal with trying to become a good Maou, while at the same time attempting to adapt to this land's customs and culture, all in a world where the tension between the humans and Mazoku is reaching its peak.
This review is based on the 17 main volumes + 5 gaidens and various other side-stories relating to the series written by Takabayashi Tomo (may sound a bit unfair but Comiket doujinshis a.k.a. Project Apollo included - doujinshi or not it's still written by the original author after all!). Will update the review as and when newer content comes out (if she gets out of her hiatus at all that is).
maru-MA is an isekai premise with some typical harem and BL elements included. The MC gets flushed down a toilet and ends up in an isekai where he is crowned as the Demon King, like
every other isekai MC he gets super powers and his own harem with an obligatory (abusive) tsundere and accidental engagement included in the package but here's the twist - it's not a harem with pretty girls rather it's bishie guys that are after him - yes guys, the tsundere is also a gay guy! So basically we have a gay version on your typical isekai harem so far but here's another twist - the MC himself claims to be straight and he does so for the rest of the series. Added to which maru-MA is like Schrödinger's cat: it is BL and yet it is not. The author herself claims that the main genres of the series are adventure and comedy and she aimed to make it Boys Gag and not Boys Love, basically implying that all the BL elements are an attempt at comedy. However her works suggest otherwise, the MC is put in a situation where he can't break the accidental engagement, worst yet the tsundere honestly believes that he proposed out of love and follows him around everywhere so that he doesn't cheat on him, if that wasn't good enough he even thinks that it is his right to sleep in the same bed as the MC and even wants to "settle" things by having sex with him. One of those attempts which struck me as pretty creepy was when he pulled the MC in bed and got over him in an attempt to have sex. The fujoshi fans will never admit to it but guess what sex without consent qualifies as rape, at least attempted rape in this case. To make matters worse even further the MC adopts a 10 year old girl (Greta) who attempted to assassinate him and as the MC's fiance, the tsundere becomes her second father, Greta genuinely believes that both of them are her "fathers" and that's yet another "reason" why the MC more or less keeps his accidental engagement at status quo, any attempts made by him to bring up the topic are immediately put away by using Greta as an excuse in the latter half. The isekai is an ideal place where homosexual relationships as just as normal as heterosexual with the maids (and sometimes even soldiers) in the castle a.k.a. fangirls (and boys) constantly betting on who the MC will end up with and shipping just about any boys they see together. It's usually the side/extra stories where such things are brought up. Most of the time they seem very inconsistent with the main plot and simply involve characters based on convenience or even fan-service. That's pretty much the bad side of the series.
Despite the shakey basis, ambiguity and somewhat of forced character relationship, where maru-MA truly shines through is the main plot line. While the beginning of the arcs may not be so attractive, each and every arc is interesting and once it picks up pace it will certainly keep you engaged. It explores a lot issues regarding what it means to be the king, politics, relationships between countries, wars, loyalty and much more. The overall plot heads into somewhat of a darker direction starting from the Caloria arc. One thing I loved about this series is how simply feelings and emotions won't miraculously solve every situation, it had a realistic feel to it (unlike its manga adaptation). As for the main plot is concerned, specially in the latter half the BL and other tropey aspects are pretty diluted and more or less take a back seat with a lot of other important things going on, unfortunately the same cannot be said about the recent content.
Tsundere comedy doesn't work well with me (seriously, what's with Japanese and these tsunderes everywhere!?) but leaving that aside maru-MA has more fun moments and quite a good mix of comedy at the right time. Even during serious situations you'll see puns and some light jokes slipping right through without messing up with the overall mood. Witty humor, play on words and misunderstanding situations is exactly the sort of comedy I love. maru-MA also includes lots of references to Japanese culture, baseball as well as other things from Earth, at first I would search about them out of curiosity later I simply found it too taxing to do so and simply skipped over the minor references or details.
The characters certainly are the heart of the series, the more characters you like the more enjoyable it will be. Most of them are quite unique and interesting in their own ways. I took quite a liking into Conrad, Gunter and Gwendal. They are not shallow and each of them has their own reasons for their actions with the exception of Wolfram who simply comes off as a completely spoiled prince, basically a walking tsundere and BL trope. Towards the end I even started liking Adalbert. The female characters might be slightly problematic however, most of them can be broadly classified as either a useless fangirl or what is supposed to be a strong independent woman (more like feminist). Gisela would be one of my favorites and I liked Anissina, too but Celi comes off as nothing more than a slut, she is the very notion of feminism gone wrong.
Overall, it was a good read. Due to the series having many characters the story keeps on switching back and forth between different character and it might spoil the mood sometimes, I noticed this specially during the the Seisakoku arc, when things are getting interesting and you want to know what happens to the MC, the story switches back to what is going on on Earth, I just ended up skimming through such chapters or skipped ahead and came back to read them later. Sometimes it's very interesting and you can't stop reading, other times it might get a bit boring or even annoying. In the latter cases it was my favorite characters that motivated me to read it till the end. Unfortunately the newer content is losing its touch and leaning more towards fan-service which I don't like, that's one reason I'm actually hoping that the author doesn't continue with this series anymore. This could have been one of best series with a very unique setting, had a lot of potential but it's unfortunate that the author decided to go down the path of tsundere tropes and fujo-baiting instead.
If you can read Japanese, then I'd certainly recommend you to read the series in the original Japanese version. Fan-translations aren't worth it.