Homosexual is an art book Osamu Sato and Hideki Nakazawa, accompanied by an animation on floppy disk. According to Macintosh Garden, it was originally sold at an exhibit in Tokyo in April 1993.
Its existence was not known to the community until leftover copies of the art book were sold at the more recent exhibition for All Things Must Be Equal. Nakazawa himself provided a disk image after being contacted.
A recording of the animation may be viewed on YouTube, and a download of the disk image as well as scans of the book's cover art are available from SatoArchives.