It sounds like you're referring to a specific Japanese adult video (AV) title or a niche genre work — possibly a parody or a themed release. The title "Koumijima Shuu 7 de Umeru Mesutachi" seems to blend elements of survival or island settings ("Koumijima" might be a fictional island name, possibly a play on "Koumi Island" or "Koumi-jima") with a numerical or volume reference ("Shuu 7" could mean "Chapter/Collection 7" or "Issue 7"), and "Mesutachi" meaning "females" or "women."
Released in the early 2020s, the series has garnered a cult following not just for its explicit content, but for its surprisingly immersive setting and distinct visual aesthetic. Koumijima Shuu 7 de Umeru Mesutachi