>>32048194Not him but I would assume it is not only because of its feminine appearance, but also because muses from myths were exclusively female spirits. Kinda how hitmons are male-only because the people they're based after are male.
Yet however, mawile can be male despite its yokai being always women, while froslass IS always female like its yokai. Machamp is clearly built as a male humanoid yet it can be female. Despite 96% of current legendaries being gender unknown, humans and/or the pokedex somehow can tell cresselia is a girl, or that heatran has two genders, or that latitwins are a boy and a girl. Yet even when lunala and solgaleo are explicitly stated to be gendered evolutions of cosmog, they appear as gender unknown.
GF has never been too consistent in this regard, so I wouldn't know for sure what they meant by this.