Japanese internet cafes (also known as manga cafes) offer comfortable lay-flat chairs. They're semi-private and have food, showers, free drinks and ice cream, a massive library of books, manga, video games, magazines and movies. They even have internet!
It's cheap to stay over night in an internet cafe. Often it's around 1000~2000 yen ($10-20 USD).
Some young Japanese live in the cafes for weeks, months or even years. Moving from cafe to cafe each night.
Most internet cafe kids are engaged in casual employment of some kind. Many find the cafes a convenient alternative to an expensive Tokyo or Osaka apartment. They may also lack the down payment that's required for an apartment (key money, deposit and agent fees often total 6 months rent).
Most internet kids aren't truly homeless. Many could easily live with parents or relatives but find the cafes convenient.
Manga cafes — unlimited free sugar, video games, movies, manga. Many kids may feel it's better than home.
Manga cafes are fairly comfortable.
Manga cafe kids lack social stability and may not have stable employment and health care. They're vulnerable to exploitation. Their few possessions may be spread around the city in coin lockers.