It has been a whole 20 or so years since this story started and it's almost 40 volumes in at this point. I've followed it since probably around 2009 or so, back when I was still in my early teens, starting with the anime version. Miraculously, while most other things I enjoyed back then has now become boring, this never failed to be a fun, relaxing and immersive read.
I've probably watched the anime 20 times and re-read the manga many times a few years apart each time, before posting this review, I watched the anime again and re-read the entire thing up to chapter 188 vol 31. That really say something. I'd recommend watching the anime first, it's pretty nice although I don't enjoy the second half too much, then reading the manga as a lot of details differ between the both, especially in the latter parts of the anime where they kind of went their own way.
What is amazing about this story is that the author, while keeping the relaxing mood, setting and comedy very similar, still manages to change it according to the times. I don't enjoy the early chapters as much anymore, but the later ones are becoming more and more interesting as the plot starts to reveal itself. We never stop learning about airantou, its various inhabitants, ikuto and everyone else. The author always manages to make every chapter feel somewhat fresh. Most of all, it's pretty much like a dreamland and I love to self-insert as ikuto, although I'd be... far more proactive if I was in his situation. I still fear the possibility of this not ending in an enormous harem, because at this point all of the central girls have been developed to a satisfying degree, most of them love him for good reasons and all of them are very likable, who you like the most just comes down to preference but you can't hate any of them.
If I had to complain about some things, the first would be the release rate. At this point, the translation is at the first chapter of volume 31 while there are several more released untranslated. I hope that they can catch up sometime or that someone will jump in and translate it quicker. From translation notes I understand there are circumstances that cause this, but I wish I could read more nonetheless.
The second minor complaint would be that there are some very clear poorly patched plot holes. I mean, I'm not reading this for the plot and it's not very plot-driven in the first place, but it does end up a bit immersion breaking with all the new additions to the cast and various settings that clearly wasn't ever in the story before, nor even hinted at. I'll just mention a few. First of all, that every single male on the island would've participated in a fishing competition is... fishy at best. It's not as if it's an obligatory military conscription and non-participation means death. With how varied the personalities, jobs, locations of the people of airantou are shown, it stands to reason that at least a few males should be left. I don't really buy it. Also, would they bring all male babies and young kids too? The explanation given for that was that only girls had been born for a while for some reason, kinda weird. The second is the background of his sister and various "coincidences" that just feel too unreal, but I guess that's what happens after so much time keeping a series alive. Then we have obaba, the old wrinkled ancient granny, that suddenly had a daughter! oh, and granddaughters and great granddaughters. She's suddenly called the big one while there's another obaba that is one of her descendants that suddenly shows up. In the latest chapter, there's a half-inumata dog youkai showing up, never having been mentioned before either.
Oh, and all the older generation (basically 25+ years and older) also start to suddenly show up after not being present for so many volumes, then there's the "hot spring association" that for some reason didn't show up because... well, they tour hot springs? On an island that isn't extremely big that can't have THAT many hot springs? Basically all the older people. So, I guess running all around the island repeatedly doesn't let you run into any of these people, they're not even mentioned. Initially, it was assuredly because the author didn't think deeply into it and just wanted pretty young girls everywhere, girls that wasn't already married with children but actual potential love interests, so he chucked all the "uninteresting" older generation out, but after long enough, they started to be needed to flesh out the story and give new tales to tell. In chapter 192, it's pretty ridiculous how suddenly, the author decides to insert a new character never mentioned before, suzu's very young "grandmother" that looks 30, that suddenly shows up after touring the island with the rest of the "grannies". Sure, the hot springs have youth retaining effects and it makes sense for them to take a trip around to some extent, but you're telling me that suzu's granny left probably around 10 year old suzu, whose mother disappeared, all alone and lonely for a few years, never took her in or even visited regularly? And not even caring that her granddaughter lives with an unknown man? Despite this, she's shown to love her very much. And she's never mentioned even once despite being introduced as being awesome at making mame daifuku that suzu loves, hell, she's not mentioned in earlier chapters as suzu is introduced as having no immediate family around her, being alone and ikuto helped her get rid of this loneliness. Yeah, not buying it even for a second. Really gotta make things a bit more believable than this even if it's to make an interesting story after running out of planned material, if it was story heavy or even slightly serious, this would knock a point or two off.
The author's standard approach to this is just glossing over it, sometimes not even mentioning it, other times letting characters go "Oh, it didn't feel important to mention at the time" and other shady, questionable excuses at best. The MC himself has been, when you look back, changed a lot too, kind of sneakily so it's not easily spotted unless you read a lot at once. For example, when he just got to the island, he was clearly thrown about by the island, being surprised at everything, having a fairly difficult time to adapt, not being that strong, making tons of mistakes and so on. But in later chapters, we're told repeatedly that he has been trained extremely much, excessively so, by his grandfather, basically thrown into various life threatening situations and having sword arts pounded into him from an extremely young age, much thanks to their family background. At the age of 8, he fairly easily fought off several adults wannabe kidnappers with a f*king wooden branch, was ridiculously agile and deceptively strong not to mention skilled, after that supposedly throwing himself into harsh training. When he arrives at the island however, he just knows the basics of kendo, has a rather weak body and is far less powerful than he's showed as at the age of 8 in later chapters. At the same age of 8(when he was reduced to that age by a time power), he was not surprised at all by his surroundings, the animals, the people and so on, since adaptability and calmness in strange new places was pounded into him from a very young age repeatedly.
So he got a massive background story power up, despite his previous time on the island saying otherwise. It did make him more likable as a character, but I kind of frown on conjuring up random backstories that don't add up like that. Oh, and his initial character quirk of denying all supernatural stuff ended up being forcibly changed, not going to mention how, so the author changed that when he tired of him being so dense in a very asspull kind of way, clearly thought up a long way into the story. Overall, he has, over time, changed to a more appealing character both in setting and actions, going from the kind of silly boy to a confident, super background, genius swordsman, smart dude that only has some of his previous quirks left, just enough to make him feel like the same character somehow.
If this stuff happened in a short manga, I'd have dropped it. But this author has kept this going for 20 god damn years and at that point, if he wants to change the story to keep on being appealing and adding more things, he has to break some eggs and he does it smoothly and gradually, so I'm definitely willing to overlook it.
This remains as one of my all-time favorite stories and I'll surely keep on loving it until the end. While the earlier parts aren't as appealing anymore, the later parts sure are. I always feel relaxed and happy while reading this, self-inserting as ikuto the natural womanizer, facing the wacky yet happy and peaceful life on airantou. I wonder how long the author can keep it going, honestly 20 years doing the same series is insane, even more so if they can keep it refreshing and fun.