kaptenkeren and I know, but other 'nothing shows ' black hair's gender in the manga: no breasts, no feminine name, no one calls black hair a girl.
I don't know why you need such thing when the title is quite literally the summary of this brief one-shot. Like, if it says it's a Yuri story, then it's a Yuri story. And I don't know why you're so pressed about the bellhop being a woman with a flat chest and with 'masculine' features. It's a funny thing to question.
Since, you're so lost. I'll give you an example:
Title: A Yuri story about two lovers in their studio apartment
Say, the one-shot shows two characters. Who are enjoying coffee together in the morning. They paint each other's nails. They laugh together at a dumb show, leaning on one another's head and shoulders cuddling close on the couch. Finally, then they eat dinner together, and head to bed.
Nothing showed that they were lovers, I mean they could've been friends. And what the heck? Did I just see one of them with SHORT HAIR? AND AN A-CUP?? Oh how will I ever know that she's a woman!! A female!! Long hair!!! Big boobs!! Big butts!!!! Howwww will I knowwww.
Read the fucking title. After you read the fucking title, reconsider in what world would a mangaka write the summary in the title and then not do what the summarized title says.
Hope this helped.