As is made evident by the synopsis/premise of the show, it is about a brother and sister (Koshiro and Nanoka), their parents, the sisters two school friends and the brothers two coworkers. Most of the time is primarily focused on the brother and sister, as it should be, and the show goes through great lengths to establish a sense of "normalcy" to the pair. They are not dislikable or unrelatable characters and for the most part they even seem to be completely rational and realistic. This is simultaneously the greatest strength of the show but also the source of its greatest weakness.
If you are going to address a topic as divisive and controversial as incest and want it to be taken seriously, then it is of the utmost important that everything remains consistently and absolutely believable. Now this is no minor task or simple feat but unfortunately I feel Koi Kaze fell short in this area in two major ways. First, the siblings. The show asks a lot from the audience in regards to suspension of disbelief. That a fully grown adult man, Koshiro, would be so overwhelmed by love at first sight over a young 15 year old girl already raises one eyebrow. The fact that the revelation of said girl being his sister does nothing to overcome his inexplicable passions raises the other. The show never makes the effort to convince you of why he would go against his surely average upbringing and exposure to social norms. In fact, it even establishes that he is not some inept sex-starved otaku pervert who longs for the touch of a woman (or little girl). That distinguishing honor is reserved for Koshiro's comedy relief creepy coworker Odagiri. Even the sister, Nanoka, shows some embarrassment when her friends introduce the idea of a "brother complex". So it is clear that there is no misunderstanding that such a thing is wrong (or at least not pragmatically desirable). That the show doesn't eschew the morality and acceptability of such thoughts/feelings is its saving grace, but it also makes the characters actions all the more bewildering. When Nanoka does a complete 180 and develops a sudden onset of "hot for brother" your eyebrows are blown clean off your face. These kinds of extreme reactions defy all reason and experience.
For the show to have any real meaning or merit the foundation must be sound and you have to convince the audience that characters are motivated by more than merely what the plot demands. That's really what it feels like when watching this. Like the plot is only advancing in order to fulfill the wishes of those who want to see the brother-sister relationship bloom. Why doesn't Koshiro ever consider psychiatric help? How does Nanoka go from regular platonic sibling relationship to a romantic one over the course of a few days (or one train ride)? Why do neither of them have interest or even try to seek relationships elsewhere? Developing a relationship with someone you've recently met and barely know is already tricky enough, but to be so instantaneously attracted to someone despite various factors and incentives to do otherwise is a very tall order. This has to be thoroughly explained and fleshed out and not something you can just hand wave away. I get the idea that since they have hardly ever been around each other that them being related is almost "not even real". Sure, but Koshiro's other coworker, Chidori, clearly lays out the hardships and misery that will follow and these consequences are very, very real. I also get the idea that "true love conquers all" but you don't just develop that out of thin air either. It'd be one thing if they had been seeing each other for a long time and gotten emotionally involved at some point before the revelation, that would at least make sense. It's hard to take back feelings once they've matured. Alternatively, had they at least slowly developed these feelings over a LONG period of time, and after trying everything else, then it could be understandable. To just shoehorn in this forced romance however is disingenuous and condescending to the audience and the show itself.
Second, the ending. I'm very critical and unforgiving about how endings are handled, and I was already disappointed by where the show went so this was crucial. For all its intent and even-handedness the ending to Koi Kaze is probably the greatest disservice. I say this because the show doesn't end with any kind of point. It doesn't try to proclaim that love is never wrong without exception, which at the very least I could respect if not exactly agree with. It just ends with a day in the life scene and everything is fine and there are no visible problems. There are multiple ways this show could have ended, but at the very least I would've liked it to have ended with some representation of Chidori's warning, making it unmistakably clear that following such a path is dangerous and alienating. But the show doesn't have any strong feelings one way or the other. This came across as intellectually dishonest, because it's clear the creator knows better and knows the realities of such endeavors but doesn't leave on such a note. To ignore this is escapist fantasy at best and naive encouragement at worst.
I watched this dubbed and found the actors to be good enough that I didn't feel compelled to go to subs. My problem was mostly with the writing and direction so I don't think there's any extra emphasis or emotion that the Japanese audio would have to make me feel any differently. The music was fine and complimented the show well. The animation was about average, varying from looking pretty good to pretty bad at times. Let me reiterate, I did not dislike Koi Kaze. I still think it was a very interesting if flawed attempt at a very daring and difficult subject. I just think had some more bold choices been made and more thought put into it I wouldn't even need to write this review as there would have been plenty of praise in its place.
