What is “Kancho” (カンチョー) ?
This is a Japanese children’s prank involving poking someone’s bum (anus) by clasping their hands with their index fingers pointing upwards like a gun. Typically, you can see kids do this among close friends around the ages between elementary school.
Foreign English teachers who come to Japan may suffer unexpected kancho attacks from children, although this is performed only from boys to male teachers. Think about it… If they did this to a female teacher, it would be more than just a joke.
(C)VisualArt’s/Key/Angel Beats! Project
This image from “Angel beats!” is the scene where Yuri (right) says “Kancho” to Yuzuru (left). She says “Onnanoko ni Ikinari Kancho Shite minasai yo” (女の子にいきなりカンチョーしてみなさいよ, おんなのこ に いきなり カンチョー してみなさい よ) in Japanese. This means “Try doing Kancho to a girl out of the blue.”
Yuzuru is skeptical about the mechanism of the world after death. In particular, He cann’t understand the principle that other students in the world after death live and act like the alive. So she suggests to do it to make sure that other students respond similarly to what they were alive. But if He runs it for high school girls, he will definitely die again.