Gorakuso was an apartment complex in Yokohama, built in 1932 by a Tokyo merchant for his daughter; after the Pacific War it became the first red-line building for American soldiers, a brothel. In the afterword Miyako Ishiuchi writes that learning these facts made sense of the thick shadow she had felt at the start, different from that of the Dojunkai apartments. The book is a counterpart to her early major work Apartment (1978), another Apartment of sorts, and brings out the other, secret history of this building complex.