Regarding the specific suffix there is no widely recognized technical or media-standard definition for this exact letter combination in relation to the term. However, in online archiving and content tagging communities, similar alphanumeric codes are often used for:
While standard ratings use letters like "R" (Restricted) or "M" (Mature), "M-R" is not a standard industry rating and may be a custom tag on specific platforms to denote a range of mature content. Legal and Ethical Context Downblouse M-R
Content grouped under letters "M through R" (e.g., specific subreddits, forum threads, or galleries). Regarding the specific suffix there is no widely