I mean, the onigiri were probably all made from the same batch of rice and they probably didn't even bother with any fillings, so the only difference really would've been shape anyway. I'd say Najimi had the right idea going for weird shapes. Might as well have some fun with it.

Though Najimi spoke twice, it didn't lie. Komi-san made pretty square ones, and it made sloppy squares.
I like to think of it as of Komi-san's masterplan to bypass all boys in the class (and that yandere abomination) and to deliver her onigiri straight to the designated person

And 0.2% deny the existence of a square onigiri.

and 1.4% are blind

98.4% of scientists agree, Onemine-san is the best.

Onemine's the best

That's really neat twist since yamai consider anything komi made is beautiful.

Najimi being a bro

So this is how an onigiri would look like in MineCraft...

Ahhh cute

It's hip to be square.

Big sis sees through everything

Oh she sees through her all right.

Ahh love the big sister friend more

ughhhh too cute

Hehehe ?