While you can use these as cheap accommodation, the main purpose of these private rooms is for folks who suddenly get the urge from looking at too much Moe stuff at Akihabara.
While peeking inside, I see rows of adult DVDs and men being handed some
Tenga before they go to their room @.@
This page shows you what its like on the inside - notice the adult DVDs and Tenga ^^;
Only in Japan? I'm not sure but dont remember seeing anything like this in London or Seattle.