Responses
I don't think she's wary of Shinobu because of their identity/looks but rather she quite literally says it, that Shinobu is a 'man' to her. In her perspective all she sees is a 'man' and warns mc that men are dangerous and will do anything to get close to women, like pretending to be a friendly okama.
I was actually annoyed when she started to judge shinobu. How are you gonna just them by the way they look ugh I'm honestly upset rn ୧( ಠ Д ಠ )୨