If this is a story that it's being translated as it updates, then there is a chance that it didn't had the harem tag cause they didn't knew it was gonna be a harem
yeah but most the time on manga reading websites, its required to have read the novel or seem all the raws, unless this one is a novel-less manga..
The novel have an harem tag to it, but the manga don't for some reason.
Either the mangas been changed or they messed up tags
P.s. this post is super long and I don’t remember at all lmao
i dont think this is harem, because it dosen't have the harem tag, and only one girl is on the cover. Or mangago screwed up with it