Just returned from an enkai, which is basically a sort of banquet commemorating a special event or just held for the sake of celebration. This one was a welcome party for me; I was in Hiroshima when this was originally supposed to be held. Enkais basically entail every employee of a workplace dressing up in their best clothes and getting completely shitfaced on sake and beer at at the nicest restaurant that the board of education can afford. The Japanese are drunk within two beers. Karaoke and laughter ensues.
But yield to the unspoken rule: What happens at enkais, stays at enkais.