Waaaa.. Since the start Ive always thought that Aoi is a man.. aghhh.. another loss for my ship.. ship has sunk, rightfrom the start..
Aoi is a unisex name and the voice in the anime is also feminine, but most people agree Aoi is a woman. I don't remember 100% since I read the older chapters where Aoi is speaking and watched the anime a year ago, but I think Aoi's pronouns are translated as they/them because in their lines they may have not used pronouns that distinguish their gender and there aren't any Japanese pronouns describing another person other than the speaker that denounce the gender of the subject (unless you literally say 'that girl/guy' but Aoi is a cat and the words used for girl/guy refer to humans). Since there is still little information about Aoi and the series isn't finished, I think it's translated this way in order not to make trouble in case a definitive gender is given later in the future.
Wait. It Aoi a woman?? Ch 73 shows that Aoi is wearing a female kimono.. Im not sure if it is a preparation for 'him' to become a princess but wearing a female kimono to send 'him' off.. well..
'He' is wearing a kimono with mon (im not sure what kind due to lack of color, maybe a mofuku kimono), obi tied into otaiko musubi (the hunch can be seen at the back of the Haori), obiage-obijime.. These items makes up the female ensemble.