Japanese homosexuals face a peculiar problem. There is a true confusion among terms for sex, gender, sexual orientation, and gender expression. As one scholar expressed it, "there isn't even linguistic space to exist in."
Like Europe, which had no real word for the orientation until "homosexual" was hobbled together in the last century, Japan has never had a nuanced vocabulary on the subject. This is because there was no need to have one. Sex with another man, or with another woman, was something you did, not something you became. Same-sex sex was more like a verb than a noun.
In our polarized, politically conscious times, however, nouns are needed -- one must be labeled. In the West the term "gay" was invented, in a kind of lingual desperation, though its use bashed a perfectly good word that had usefully combined "happy" and "cheerful."