Akasen

Akasen (赤線) was the Japanese slang term for districts historically engaged in the sex work industry in Japan, specifically within the time period of January 1946 through to March 1958.

In Tokyo, the area directly across the Sumida river from Yoshiwara (Tamanoi, now called Higashi Mukōjima) was a well-known aosen district; it features in some of Kafū Nagai's short stories.

The order also had the effect of disbanding the short-lived Recreation and Amusement Association, which had, for a period of one year, worked to ensure that sex workers were not abused and exploited by stationed American soldiers, amongst other things.

Due to GHQ orders, brothels - often numbering in their hundreds - began to front non-adult faces of their businesses (such as coffee shops, cafés and beer halls), but would offer sexual services to customers, creating new avenues for the sex industry to continue, especially in popular districts such as Yoshiwara, the akasen region of Tokyo.

In 1958, the Anti-Prostitution Law (売春防止法, baishun-bōshi-hō) was enforced, thus officially abolishing legalised sex work, the red-light akasen districts and their label of 'akasen'.