Hebi is the Japanese word for snake, and I have become afraid of it, not of snakes but of the word.
If a child with says “hebi”, it means that they are going to try to shove their hand up your bum, a completely violating experience. I have a new pavlovian reaction and respond with “Dame!” Which means don’t do it, but the children rarely listen.
Americans have 2 similar ‘games’ goosing and EB (elephant boner). The first is just like the Japanese ‘game’ the other is where you violently knee someone in the bum. They are horrible games in which I participated, but I would never have in a million years done it to an adult, and especially a teacher.
The children here are fiends, I have seen them do it to anyone and everyone, to the point where if there are children around, I find it safest to just sit.
I’m not sure if this is a nationwide phenomenon, or if Uenohara kids are just particularly fond of butt snakes, but I hope it is a phase that passes very soon.