Apparently, the Japanese aggressively despise being recorded or photographed without warning but are generally okay with it as long as you clarify that you're doing it so they can pose or do their thing. This translates 'okay' to overseas audiences but not entirely.
How to troll freinds while they are sleeping in class *Take photos and record them* *Me who smacks chair on my freinds heads*: Oh! I have been doing this wrong