This was a show I picked up on a whim one day after seeing it on many lists of "anime that will make you cry". I like a good emotional story, so I figured why not? I was not prepared for the emotional rollercoaster that this show put me through.
Kousei is not necessarily the most relatable protagonist, since most people aren't familiar with the feeling of performing music alone in front of a crowd. However, the way the show portrays his suffering and anguish when he is unable to perform the way he wants to makes the viewer feel like they are in his shoes. I found myself genuinely feeling a sense of relief when a few particularly painful scenes finished and Kousei exited the stage - the kind of relief you feel when you finally deliver a difficult speech, for example. Additionally, I felt so joyful and elated when he delivered a good performance.
I have never been a fan of tsundere characters, or characters that abuse the protagonist in general (for example, I never liked Sakura from Naruto) and unfortunately, Kaori did not change my opinion on this. I found it somewhat annoying when she would mistreat Kousei, but these scenes were always very brief and didn't impact my enjoyment of the show. If anything, it made both Kousei and Kaori more teenager-like, and helped sell the idea that they're still only thirteen year olds.
Now, about the emotional rollercoaster part. This anime will have you crying, then cheering and clapping, then sobbing your eyes out like a baby, all in a few episodes. And this cycle happens over and over. I almost want to watch it a third time just to see how many times I actually cry. The ending makes the entire cycle worth it, and unless you are entirely void of emotion, you WILL be crying when you watch the last episode. The first time I watched it, I was outright bawling the entire time. It's a bittersweet end, and one I haven't experienced the likes of in any other anime. It will leave you heartbroken but also hopeful, and of course, you'll have a big fat pile of used tissues next to you.
Overall, I highly recommend this anime to anyone looking to feel a connection between themselves and a group of characters. Kousei's victories are simply wonderful to watch.