Story: 10/10
It is a slice of life manga at its core, and the story is almost non-existent. Each chapter basically follows the same template - two high-school boys hanging out after school near a river bank and having mundane conversations, sometimes involving supporting characters. Not dissimilar set-ups have been used many times before, so what makes it different? The answer is how the author has used this set-up to his creativity. There are sometimes chapter where the same situation on riverbank plays from different vantage points to surprise the readers; sometimes an expected character shows up instead of our two protagonists; sometimes many characters involved in seemingly different activities on the riverbank end up getting caught in each other's way; and so on.
But the reason I gave the story a 10/10 is because of the writing. I am not sure if I am supposed to include that here, but I am going ahead with that for now. The dialogues and conversations between the two boys, Seto and Utsumi, and by far the strongest aspect of this manga. They are clever, funny, inventive, and written in a very simple style to cap it off. Many different manga equates clever writing style with complex writing style (you know, where they strive for complex word plays and unnatural dialogues), but Setoutsumi keeps it simple, easy to read, and (something I don't really like to use for a manga or anime) relatable.
Also, if you (understandably) still confused why this warrants a 10/10 story, you have to read the last 4 chapters to understand it. I won't be giving any spoilers here, but the ending of this manga is what made me give the story a 10. For a slice of life, you can never expect the writing to be so tight and uniform in quality.
Art: 7/10
Nothing of note here; the art is pretty much serviceable for a manga like this. Character designs are simple and relatively realistic. Characters don't look as beautiful as Katsuzo Hirata's, but neither as ugly as Taiyou Matsumoto's. They are average looking people which serves well for the whole theme of two average Japanese high school boys well. It also doesn't have any exaggerated facial expressions or physical reactions of straight man routine for art to shine (as in something like Grand Blue).
Character: 9/10
Though eighty-percent of the manga is just about two characters, it never gets boring. Both the characters have a very generic character traits - Seto is the outgoing, loud, idiot character while Utsumi is the apathetic, intelligent one. However, the realistic execution of these generic traits somehow makes them feel unique. Like, Seto is a loud character. but he doesn't go about yelling all the time. Similarly, Utsumi is apathetic, but it doesn't mean he couldn't be funny or couldn't be aware of his surroundings. And both of them are written with an impeccable consistency throughout.
Supporting cast is a bit meh. Even though both protagonists may also appear one-dimensional, we spend enough time with them to understand them and appreciate the nuances of their traits and discover more aspects of their personalities. Rest of the cast is pretty much one note with a particular role to serve, be it a love interest or running gag.
Enjoyment: 10/10
Here, I am only putting my thoughts without trying to be objective. The comedy is great and perhaps one of the best I have read in some time in a manga. Not declaring them bad or anything, but I had grown tired of comedy manga's attempts at comedy being limited to familiar situations, an irritatingly loud straight-man routine, exaggerated facial expressions, chibi forms, or a combination of all these. Compared to them, Setoutsumi feels so much refreshing and even more hilarious.
Something else that I really enjoyed is how well it did its Slice of Life parts. Most in the genre have a problem which i have grown to hate - a series of simple, chill moments is suddenly interrupted by a dramatic chapter which is, more often than not, heavy-handed and jarring. Setoutsumi has many similar pitfalls. However, it avoids all of them and when it comes to handling drama and transition, it did it rather smoothly.
For the sheer ingenuity of what appears to be a generic Comedy/Slice of Life to manage the tropes and execution this well, this manga deserves more love.
Overall: 10/10
A little biased? Maybe. I won't go ahead and say that everyone will enjoy this as much as I did. But if you like either of Comedy or Slice of Life, I would be surprised if you don't find this interesting.
TL;DR: Really funny manga with dialogue based comedy, strong writing, and totally deserving of your time. Not really long either (I completed the whole thing in 5 hours). Also, read the whole thing; it has a (rare) amazing ending.
