Hikikomori is a Japanese term that, like sushi and sake, or more to the point, hibakusha, has entered the world lexicon. It refers both to the phenomenon and the individuals who suffer from “acute social withdrawal,” defined by the Japanese government as youths who isolate themselves in a single room of their parents’ home for six months or more. Estimates of the number of hikikomori vary widely, from several hundred thousand to over a million, but there is no denying that it is a major, and growing, problem confronting contemporary Japanese society. Most of the hikikomori are teenagers, eighty percent of them male, who often begin by refusing to go to school and then cut themselves off from social interaction entirely.