Kaguya-sama wa Kokurasetai: First Kiss wa Owaranai fails so hard as a movie. That's the biggest con of it. It's more like a mix of several stories put together, with one or two themes receiving more attention than the others, but not as huge to leave an impression of this movie being actually a movie. Episodic version of this movie is somewhat bearable, even if it feels so much like a set of four special episodes, serving as an extension of the previous season. But hey, this version was created later, no? If I decide to review a movie, I need to treat it as such, because the show that's being reviewed was intended at first to be experienced in that particular format. As I said earlier, this movie fails in encapsulating pretty much most of the elements you'd expect to see while watching a movie.
As for production quality, it was decent. The previous anime adaptations presented already pleasant quality. The movie was no different in this aspect. One would point out that it should've received better animation, because movies, due to various reasons, tend to have animation representing a higher level than regular TV series. That's true, however, TV series already looked alright and all previous seasons were mostly carried by fancy direction and vibrant colours used in the art style. I think it'd be necessary for a movie to go a different route for the sake of being different and going somehow against technical tropes already enjoyed by the majority of Kaguya-sama anime fans.
With similar quality to the previous Kaguya-sama franchise's anime installments come as much positive, as negative things. This movie had everything I disliked about Season 1. Repetitive corny jokes; characters yelling and squeaking most of the time while talking with each other; narrator ruining the flow of this movie even during its objectively best scenes. Yes, I know these elements appear in Seasons 1-3 as well, but at least they present bigger variety and hmm... mature? I think it's a good way to word it. The same joke evolving over the time is alright, but devolution of it, in consequence, resulting in the decrease of overall comedy quality, is something I'm really not a fan of.
So, in conclusion, I did not enjoy watching this movie. It's sad to say, but "The First Kiss That Never Ends" can't be really perceived as a good movie by viewers like me. I'm not a manga reader and I didn't like the previous seasons that much. I expected to watch at least a decent, solid, proper movie. Too bad my expectations weren't met, and I think that as long as you are not a devoted fan of this series, your experience has rather a huge chance to be most likely similar. Maybe a little better, maybe a little worse, but still underwhelming by a huge margin. With having everything written earlier in mind, I just can't recommend it. Not for people who are not devoted fans of this franchise, or who simply wanted to see a cute movie sequel to a series they were once watching. That being said, if you are already a huge fan of this franchise, dear reader, which is of course fine, then I think there's a huge chance that you're gonna actually like it. No matter whether you will decide to watch it in the original, movie format, or in the episodic one. Sadly, I'm not a huge fan of Kaguya-sama series. Not a hater as well. I'm just a regular enjoyer of this series. And I just wanted to see a good movie.
