: This is likely a reference to "SOD" (Soft On Demand) , a well-known Japanese adult media producer. The "604" may refer to a specific volume, series number, or internal tracker ID.
: Often indicates a bitrate (e.g., 500kbps) or a part of a larger collection. sodopen604 500 sex 20060504avi exclusive
If you encounter actual files matching this name, approach with caution and critical literacy. : This is likely a reference to "SOD"