>>92359
I believe that was the term I meant, however, I have heard it summarized as the argument of false dillema. Whatever.
In any case, I still say that this is such a case. The lesbians or !lesbians argument is too vague. For example, could not SOME of the group be lesbians, and some not? If Tomo were gay for Yomi, must Yomi be gay for Tomo? The OP offers 2 choices: All the girls are lesbian, the girls are not lesbians (suggested by the title "...are ALL lesbians")
Similarly, this leaves out the idea of bisexuality. And let's not forget, asexuality. In Chiyo's case, she's too young to really grasp sexuality, anyway. Or, we could go with a more realistic option: "Unknowable"
Since we can't see inside the heads of people who don't exist, and since we did not witness any scenes involving their romantic contemplations, it is impossible to know if they even have any.
And to the thread in general, what about Nyamo's sex talk? It was obviously about girl on guy, and the girls ALL seemed interested. She was, presumably, speaking on heterosexual intercourse, causing lots of blushing. Does this not demonstrate some evidence to heterosexuality? Is this argument as baseless as the lesbian side?