Nah, pogotun is right. I love yuri and boobs but this manga was painful.
The main girls have no relationship dynamic beyond "has boobs" and "likes boobs" and then later develops into "also I think she's cute fr" ... the secondary couple is a lolicon and her loli, the third couple is a weird pairing of a girl who deeply disrespects the main girls' boundaries (never is held accountable for this btw) and a girl she sexually harasses into loving her.
Also there's a creepy cousin who, if we're going to take this more seriously than it needs to be, absolutely groomed one of the main characters into being obsessed with genitalia lol. It's played for laughs but "I talked to my ten-years-younger cousin (age 6) about my love for titties (drool emoji)" is just all kinds of uncomfortable the moment you actually think about it.
But it's not serious. This is just a shitty little self-indulgent manga about boobs. If you go in expecting anything, and I mean ANYTHING, more than seventy boob jokes per volume, you're in for a bad time.
My biggest problem is that it's billed as a comedy, but there's maybe two or three punchlines total in an eight-volume-long 4koma series. The punchlines are, in order of most used to least used, "boobs," "she doesn't like ME but my BOOBS?", "she's a lolicon", and "boobs". Oh, shit, did I repeat that one? My bad, I shouldn't do that seventy times in a row over the course of eight volumes of literature
Kombu clearly loved boobs and wanted to make a manga about boobs, so she did. The manga kinda sucks, but it's also exactly what she set out to create (I presume), so in a way, it's perfectly fine. I can't hate it, but I sure as hell didn't enjoy it myself lol.
When it comes to "boob manga" (whatever that is), I'll always recommend Saki because it has insane boobs courtesy of an author that clearly has a major obsession with them, but also has meaningful relationships between girls and a well-driven plot constantly developing. You can also try Otome no Teikoku, which, despite its episodic nature, somehow manages to develop its simple but endearing cast well beyond anything that gets accomplished in eight volumes of SekaOppa. It also acknowledges parts of the body other than boobs ALONG WITH boobs! Amazing.