Japanese actually never have the context to describe their sexuality at all. Bi, Gay, Lesbian, Pan, etc. were never in their vocabulary. Everything they see is described as physical appearance. That concept is pretty new to them even to this very day.
ニューハーフ(newhalf) = Trans people, practically half-man/half-woman
男の娘(Otoko no ko) = is a synonym to 男の子(boy) that reads the same, pretty much tomgirl/femboy.
やおい(Yaoi) = Boy loves, a love between men (basically gay but as a genre for media's label, not sexuality)
ユーリ(Yuri) = Girl loves, a love between women (same as above)
あねシ〇タ(ane-sh*ta) = A loves between a woman and a young man (very, very young)
Etc.
And the one people always misuse, mislead, and misunderstanding is ふたなり(Futanati).
ふた(Futa) normally isn't a bad word on its own and is used in various wording.
ふたりとも(Futatitomo): Both of them/you, You two
ふたたび(Futatabi): Again, Once more
ふたつ(Futatsu): Two, Both
Etc.
Last but not least, ふたなり or Futanati, word by words, means 'Got both', which properly translates to 'Hermaphrodite', referring to certain individuals/creatures that MUST have both genital, no matter if they appear as man or woman. And Cuntboy isn't even a proper word, they use it word-by-word based on English words when referring to those that appear, from any angle, a male individual but only have a vagina.
TL;DR: If they have only ONE genitalia, they are NOT futanari, they're either trans or the other way around. And if they are not human (slime, blobs, tentacles that form humanoid bodies, etc.)then they're androgynous or genderless by default. That's pretty much it.
Is it gay? I don't freaking care, I'm bi. Gender appearance is no longer my daily life concern. Ask your own soul. Not other's validation. If you feel repulsed by it, just click that X symbol and call it a day, it's that easy.
