the only thing y‘all should be mad about it that he touched high schoolers, not his personality. they are adults, they seem to like each others personality. This is just showing how it is, people have flaws and are not your ideal fluffy characters you see in mangas.
if you ignore the slightly perverted curious kid there's nothing bad. no sex no predatory behaviour no pedos or anything. Some ambiguous moments (but no harm whatsoever) the manga is mostly about how their universe works
There's no sex, no dicks, no Masterbation, only thing in here is occaional groping and sexual innuendo. Just a bunch of short read in any-order stories with the only goal is to have a slight-half-harded giggle.
I mean 3 year differenc eisnt bad....but when one of them is 13 Ím callimg the cops