This review will be heavily referential to the original series of Binan (I'll call it 'LOVE!' from here to differentiate it between this newer series), since it, you know, has the same name and is basically just the same story with a different cast and some new effects and designs. That original series, despite being some criminally obvious fan service pandering, is in my opinion absolutely fantastic, and not just because the cast directly caters to my tastes. I genuinely do think the writing was solid in every episode - it managed to comically deal with pertinent social issues in a mature but light hearted way, and Yumoto's little monologues at the end of each are great. I would love to have watched it as a high school student, I think I would have gotten something out of it (beyond the fudanshi pandering, I mean). The surprising competency of its writing is probably why the original series was a bit of a surprise hit, and in turn that fanbase is probably why Happy Kiss! exists. The staff could have been content to just phone the entire show in, but the effort resulted in a rare combination of a show entirely catering to one specific demographic via excessive fan service while also being entertaining and well paced.
Turns out you can't bottle lightning! While the 2nd series of the original LOVE! suffered from a marked dip in quality writing wise, to mend this hole in the hull the writers turned to even more fan service (and an over reliance on Yumoto, probably incontestably the star of that show - notice he's the only one with a cameo proper?) and a reliance on your attachment to the cast it worked With Happy Kiss that isn't possible, because this is a whole new cast!
I think it's reasonable to focus heavily on the characters. As I mentioned in the introduction, this anime is just a retreated of LOVE!'s story - not literally but enough that you won't be watching it for its plot. That being said, the new cast is...a mixed bag. I have to respect the writers for refusing to take the easy route and try to just remake Yumoto, but the boy to fill the colossal gap he leaves, Kyotaro...Well, I think he might have ignited a hatred for the 'constantly yawning, oh-so-sleepy' archetype in me forever. I think I can see his intended role. His apathy and indifference is supposed to be cute, and perhaps he is meant to be a parody of some kind of zen master. But in practice, replacing the pure hearted and irresistible sincerity of Yumoto is an incredibly bored and indifferent guy who doesn't seem to care in the slightest for the people/monsters he is fighting with is very jarring. Maybe if his visual design appeals to you his mannerisms are less offputing - but I found myself at times pretty frustrated with the way he acted. It just did not seem in the spirit of the franchise I've grown so attached to.
On the other hand, Kyotaro's weakness as the male lead allows the rest of the cast to shine a bit more than they could in LOVE!. But...not really enough. Taishi and Ichiro's sparring seems more natural than Io and Ryuu's - mostly. Sometimes it feels as if they weren't sure whether the two were supposed to be shipped or at odds with one another. Further complicating this is Ichiro's relationship with Nanao, another character who I appreciate for his deviation from the standard (a weird, demure sadist who is also very kind, an interesting combination), and who is clearly intended to be bait for shipping with the infatuated Ichiro. But, as confused as these relationships are, they are at least that: relationships, The rest of the cast, it seems, do not have much of any! Kyotaro talks to to his incredibly bland, and I hate to say it, but completely pointless ginger friend Ryouma, and that's about it. I cannot remember a single time Ryouma spoke to anyone but Kyotaro - he may as well be his stand for all his relevancy to characters beyond Kyotaro. While not quite to the same degree as Yumoto, the incredibly cute and cheeky student council member Martha steals the show. It feels as if this was something the staff too were aware of - he is the only character, outside of Kyotaro and Ibusuki, whose rift forms a great deal of the plot, that gets any kind of episode devoted to his backstory, oddly.
Other strokes of consciousness in the writing staff seem to be in the Wom-san replacement's writing - Karl, the cute yellow otter, is really great. He adds quite a bit of energy to the show, and were he written to be more lethargic or cynical I feel like I would hate this anime. His design (as a human) is also very cute - if a little pointless, given that it only exists in transformations and in very brief scenes. I also enjoy the novelty of his backstory - I feel it melds better than LOVE!'s strange (albeit amusing) focus on aliens and the galaxy and television. It is just a shame that the writing was not brave enough to try and focus more on that setting, and instead chose to retread the same structure of season 1 (I am not exaggerating, it is ludicrously similar).
Hyonyanaland, Karl's homeland, appears in the finale and its scenes are a highlight. It provides a welcome diversion in visuals and is greatly helped by some great music, an area I have as of yet neglected to mention, but one that I feel is a clear improvement over LOVE!. The transformation music is exciting and fun, but even better is the attack music - the poppier and more upbeat melody and style are well suited to the less earnest and sincere tone established. The "attack" sequence is only really hurt by Kyotaro's voice acting. While I think the seiyuu does a fine job regularly, here...well...It is quite laughable. The voice he uses is not suited to the bellowing. "Rab is oba!!!" it is not, that's for sure.
Speaking of the transformations...They are fine. I like the kissing theme and the use of water (makes sense - Karl is an otter remember). Not so much the visual designs. While they are not terrible, the lack of deviation from the previous series is a bit disappointing, especially given that this isn't even supposed to be the 'battle lovers' anymore - so why do they look so alike? What's more disappointing is the student council costumes, the Furanui knights, which - well they ARE terrible, especially when compared to the original student council costumes, which were fantastic and better even than the main cast's'. That being said, visually Happy Kiss isn't a huge decline. There is still the eternal sidemouth which is a pet peeve, but it looks a little better than season 2 of LOVE! (although not quite as good as 1, in my opinion). It's a sugary sweet, colourful anime with a cast entirely made up of bishies: the visuals reflect it more than adequately.
The impression given by this review is probably that I hated this anime, but that's absolutely not true. I am critical of it but I still watched the whole thing and had a fun time doing so. It is only because I so enjoyed the original that the flaws in it become jarring. If they announced a follow up it's very likely I'd watch it ASAP. If you were a fan of the original show and its concept (not solely its cast) I am sure you will enjoy Happy Kiss!, but maybe not quite so much as LOVE! or even LOVE LOVE!.