From Hagakure: The Book of the Samurai:

If you cut a face lengthwise, urinate on it, and trample on it with straw sandals, it is said that the skin will come off. This was heard by the priest Gyojaku when he was in Kyoto. It is information to be treasured.

What this means is… Holy crap! What was in this guy’s sake?
Eww…