Chotto Otona no Naishohanashi - Vol. 1 Ch. 3

[MangaDex]

 

[MeePotato]

very much a cnuy chapter

 

[bagong016]

yeah, bend their common sense so it'll be easier to turn them into a perfect ona--

 

[mailforporn]

6th grade is at least 3 years too late to not feel embarrassed by boy-vs-girl stuff, even in a backwater place with no one fussing about it or explaining how things "should" be. even without external influence most of the kids would've discovered masturbation and thus sexuality on their own by then and even if they were stopping themselves from it, it'd be precisely because of embarrassment, not the lack of it.