Completely wrong thing for publishers was to call it "horror"(for the sake of marketing), assuming there is some fun in gameplay for narrow-minded crowd. Much more like "psychological". Should not be called horror at all. In fact it is 100% yuri drama, as we know now from ddlc+
^I usually see it described as "psychological horror", which I feel is pretty accurate. There are absolutely horror tropes throughout the game, along with a handful of jumpscares.