The way they handled childhood friends in Manga you'd think that out of 10 people in Japan 9 of them have a childhood friends that's tsun-tsun.
I am just wondering whether it really is a common phenomenon in Japan and not just otaku-pandering because where I live stuff like that doesn't exist.
Otaku pandering that almost doesn't exist.
I'm pretty sure there are some authors that speaks from experience of themselves or their friends, but you'll be able to notice the difference than the usual childhood friend stuffs you usually see.