Tokyo, 2034 AD. The march of modernization has continued unfettered, and many things have changed. One example is money. In the year 2029, an electronic money system was introduced nationwide and, as a result, people no longer carry cash on their persons. The money is controlled by someone whose identity is unknown to the average person. All that matters is the question "How much can I spend this month?" and ensuring that they do not spend more than they have available.