Beware of spoilers from here on out:
"Protagonist x Rival" is a short story, despite having 4 volumes and 47 chapters. From what I understand this manga began his life as a WebComic in May of 2019 until April 2020 when it was serialized by Gangan Joker. I mention this because even though the art was improved for the serialized version, the length of the chapters was not what caused several chapters to be short stories (approximately four pages long) about the characters in random everyday situations. Is this a bad thing? Not necessarily, since this manga is pure comedy with zero drama, so this manga manages to make you smile even with four pages. Now, comedy is quite subjective in most cases(what makes me laugh doesn't have to make you laugh) and in this particular case the comedy is quite childish and repetitive. Almost all the chapters follow the same pattern: Kimura tries to get close to Mizushima, to deliver Valentine's Day chocolates for example, and Hiyama apparently interferes by bullying Kimura, only to discover that what she really wants is to express her love for Kimura which she does in a rather clumsy and very aggressive manner. And this pattern is constantly repeated throughout almost the entire manga.
Objectively speaking what I just wrote is true, which for some may be a negative point for the story, for me personally it is not so much. I really love the interactions between Hiyama and Kimura and they make me laugh out loud in every chapter. Kimura's shyness and low self-confidence and Hiyama's social awkwardness lead to many hilarious misunderstandings.
The strongest point of the manga is without a doubt Kimura herself: her progression is more than evident, in each chapter she gradually overcomes her shyness and little by little she discovers and understands her feelings towards Hiyama. There is a huge difference between the Kimura that we see in the first chapters of the manga and the Kimura that we see at the end of it(they are complete opposites). With this I do not mean that Kimura's radical change is a bad thing, in fact it is quite the opposite, it is very satisfying.
Hiyama doesn't really change much, she pretty much stays the same throughout the entire manga. Thanks to Kimura's radical change we are also able to see Hiyama's true face: behind her aggressive, strong and self-sufficient attitude that she shows at the beginning we discover a rather innocent and shy girl at the end. Put this way it shouldn't work, but it does and I promise it makes sense.
The other characters are not worth mentioning... Mizushima is only there to help the plot move forward. And the others, like Kimura's friend or Hiyama's two classmates, most of the time just serve as comic relief. I'm not saying they're bad, for example all of Tatemoto's interactions with Hiyama are hilarious, I'm just saying they're not very important to the story(except for Mizushima who is important and necessary).
Summary: "Protagonist x Rival" or "Shoujo Manga Shujinko x Rival-san" is probably a manga that you can read in one sitting in just a few hours, it's fun and heartwarming, full of fluff and absolutely no horny moments(no bra or panty flashes...sorry). It's just an innocent story between two girls who discover their feelings for each other... and once in a while that alone is enough.
The score is probably too high (maybe 7 or 8 would be more appropriate), but I love this manga so much that I can't be realistic about it... but thanks for reading anyway.
