If you are looking for specific content, it is highly likely that this term is associated with specialized content-hosting websites, file-sharing platforms, or niche forums. To find what you are looking for, you might try searching this exact string in a search engine within quotation marks (as you provided it) to find the specific digital repository or community where this file or video is listed.

Likely a date or unique ID generated by the hosting platform.

[ Studio Prefix: SONE ] - [ Release Number: 290 ] - [ Metadata Tag: SUB ]

In internet searching, strings formatted like this represent programmatic index terms used by adult streaming sites, aggregation platforms, and torrent networks.