Seriously? That was a rhetorical question. Obviously anyone that doesn't see the issue here needs to be put on a list. This manga started with a time skip where we meet their high school selves who have matured quite a bit so it makes sense that they'd be behaving like the horny teenagers they are at that point in time. Now all of sudden we go back in time to the period of the official work where they're still a bunch of 10 or 12 year olds. Only a child predator would would find it normal for them to be behaving the same way.