As far as love stories go, it's often very hard to come across one which feels real and that a viewer can actually relate to, I find this even harder in anime. That said, Say I Love You does a surprisingly good job at being a down to earth, relatable, love story, and that's really what made it the best in a season full of romantic series.
We're introduced to Mei, a shy high school student who keeps to herself and doesn't really have any friends, let alone having a boyfriend. Then we have our lead, Yamato. Yamato is the most popular guy in the whole school and could have any girl he wanted as a girlfriend, however, our star falls for shy Mei after a certain incident has the two bump into two each other. The feelings go both ways and within a couple of episodes Mei realises that she two has fallen for the charms of Yamato and really likes him. This is one of the better aspects of the series, because only the first couple of episodes are spent on Yamato and Mei realising how the feel, while the rest are far more focused on the trails and troubles a young couple run into, of which there are many. It's quite hard for Mei to get used to Yamato's attention and often wonders why he'd fall for a girl like her when there are far prettier girls in the school, the show also has Mei make friends with a couple of other girls and does a good job of showcasing the fears one has when being around people they'd consider friends for the first time. Mei has to learn that her friends are there for her and that she can trust and lean on them when needs be, all of which is taught in a respectable way and I feel like the show couldn't really have done better at it. This isn't to say Yamato doesn't have troubles of his own, because he does, and while you can start out seeing him as somewhat of a jerk, once you learn about his past you quickly realise you may have judged too quickly and too harshly on Yamato for all that he's been through.
However the show doesn't drag out the inner feelings and fears Mei and Yamato have for nothing, about halfway through it introduces new characters just to bring out these feelings and for us to watch how Mei and Yamato are going to deal with it. One of these characters is Megumi, a really popular model who transfers to Mei and Yamato's high school and quickly makes it clear that she has feelings for Yamato. This arc of the anime does a very good job of showcasing how a young teenage girl like Mei could deal with being jealous, but to a point it also begins to focus on bulling as the story goes on and begins to focus on Megumi, which is a nice change and also hits home how real the anime feels with its plot. Maybe that's what so refreshing about Say I Love You, the fact that it doesn't sugarcoat anything or throw in needless comedy to soften the blow, it takes itself seriously and shows you everything hoping that you will accept it that way, which is really the best thing it could have done. Mei feels very much like a real teenage girl facing the fears and feelings that a lot of us will face nowadays and it's refreshing to see such a character that can easily be relatable to by modern day girls. Yamato feels a little less real to begin with, purely because he acts like a jerk (much more so than in the manga of which the anime is based off of), but by the end of the series you can happily accept him too.
In terms of animation the series gets it just right, nothing is too flashy, and everything feels down to earth and fitting for such a series. It isn't to say the animation is bad, because it isn't, it's more so that it doesn't go out of its way to be needlessly flashy and impress, settling to be quietly impressive in what it actually does. Character designs aren't all that flashy either, Mei has a simple but cute design, while Yamato and Megumi are both made to look like they would be the popular kids, but there designs aren't made over the top either and again everything seems to slot together nicely.
Where music comes into it the opening theme is very slow and pretty, quite fitting for the series, the ending theme is a bit more up-beat and slightly less fitting for a slow love story, but in the end that doesn't feels too much out of place where it'll spoil anything. The overall soundtrack for the series doesn't stand out too much, with nice piano pieces here and there just to add to the moment, but never being the centre of attention. The music here isn't there to stand out, more to blend into the background and help the scenes as much as it can, which is does mostly flawlessly. You likely won't be remembering it for years to come, but that isn't to say it hasn't worked well for the series.
Say I Love You ends pretty fittingly for its characters and plot. The manga is still on-going and thus more could be added to the anime if they wished to do so, but the series was ended in such a way where you can want more, but also be perfectly happy with what has already been done with the series. The series is a pretty perfect down to earth love story, the likes of which haven't been seen in anime for a couple of years now, and it's always refreshing to see something that didn't need comedy or flashy moments to be a really special show for the viewer.