The subject line appears to be a file name or title for a specific adult entertainment video scene. Here is the breakdown of the metadata contained in the string:
One possible interpretation of "lustery e1609" is that it refers to a mysterious product, software, or technology that has been shrouded in secrecy. Alternatively, it could be a codename for a creative project, art installation, or a musical composition. lustery e1609 joey lee and mav swing and a mist