As you may know, idolmaster has several sub-IPs (classic, dere, mili, shiny, side-m, etc.), and various works derived from each sub-IP are released too.
Among them, idolmaster_cinderella_girls_starlight_stage and idolmaster_million_live!_theater_days, which were released as rhythm games, are famous, and recently, idolmaster_cinderella_girls_u149 is being aired as an anime in the second quarter of this year.
This topic is about the last in the line of high (idolmaster), middle (cinderella_girls), and low (u149) copyrights.
Looking at the recent posts about U149, I noticed that some people have added the U149 tag just because the character belongs to that copyright, without any relation to the aired anime scene. Is this correct?
In my opinion, like the tags for rhythm games and the tags for anime, we should only add these tags to posts that remind us of a specific scene (post #6201563, post #6260144), or posts about costumes that can only be seen in that game (post #3872454 post #6222023). I also think it's appropriate for people to add the tag on a case-by-case basis, when they're really thinking of that particular scene, that particular costume, rather than adding it to every post.
If you think a costume is confusing, try searching for the official_art for that character. Of course, we don't have all the official_art on Danbooru - I only upload the ones I think are pretty - but it's well organized on sites like the game DB site.
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