DFW examines this phenomenon, obtusely, in Infinite Jest. None of his characters are Hikikomori (and honestly a book about someone sitting around and doing nothing sounds a tad boring and self-absorbed, but I'll have to read Leave Society to find out), but they are all forced to deal with a world over saturated with drugs, politics, sex, tennis, and the TV/video media.

Orin, the main character's older brother, becomes a semi-recluse/sociopath, which is the closest character to an explicit Hikikomori DFW paints in the book. The other major characters rely on other forms of relief to cope with their anxiety, depression, family issues, etc.

DFW wrote Infinite Jest in 1996 before the internet truly took over. I'd love to see another book tackle the issues and repercussions of internet-soaked culture the way DFW tackled the nature of addiction in Infinite Jest.