Spring of Birth is the first in the series of anime films that adapt the story of Persona 3. I was worried when I initally watched it, about how they were going to take an overarching video game movie, and split it up into four 90 minute movies. The end result isn't perfect; this first movie definitely has pacing issues. Specifically, it feels akin to a drawn out "set-up" prologue that just explains the world and what the hell things like the dark hour and shadows are. Which is basically what it is--this first movie adapts the first portion of the game's story, up to the point when Fuuka joins the SEES. In an attempt to turn what would've been "exposition - the movie" into an a movie that can stand by itself, they put focus onto both the development of Makoto (the protaganist), an an unusually apathetic guy who doesn't care if he lives or die, and the substory in Persona 3 surrounding Fuuka's bullying problems.
They set up Fuuka's bully issues with Natsuki, as well as the overgrowing issue that Makoto struggles to (or rather just can't) feel emotions, as the throughlines of the movie. The two intertwine, and form a pretty decent overarching narrative that gets resolved by the movie's end. The end result, while not perfect, works well enough, and results in a deeply entertaining adapation; it sets up the world of Persona 3 itself, and the base premise, while wrapping up it's own internal conflicts, so that things to normality for the protaganists for the sequel.
Honestly, despite this being an unpopular opinion, this is my personal favourite film in the Persona 3 film series. Not only do I adore the way they adapted Makoto's "silent protaganist" character, I also think the atmophere of the movie works extremely well. Fuuka is one of my favourite P3 characters, and her bullying issues; as well as Makoto's character arch too, fit extremely well with Persona 3's blatant symbolism surrounding teenage sucide (Persona users need to "shoot themselves" in the head with their evokers to summon their personas). All in all, it comes together to form a very decent movie, that is essentinally a "mean girl" bullying storyline set in a world full of supernatural goings on, where the bullying gets dragged into the events the protaganist & co. Are going through. It can stand on its own, seperate from both it's sequels and the game it was adapted from. It's far from the best written example of a bully storyline, but honestly, the relationship between Fuuka and her bully by the end of the movie legitimately touched me; not to spoil anything.
Honestly, I think people are too harsh on this movie. Most critics seems to focus on it's slow crawl of the overarching P3 narrative, and either miss, or discard, the movie's attempt at forming a complete story that deals with connected themes of suicide, bullying, mental apathy, and death; albeit one that is part of a larger overarching narrative.
I'd legitimately recommand this to anyone who wants a movie that deals with that kind of thing, even if they're a none Persona fan. Just bare in mind that it's story isn't complete, as it's one big overarching story spread over it and it's three sequels.