Demon of the Rift in Final Fantasy V. Disguises as a damsel in distress locked in a prison cell with Catastrophe. After the party defeats Castrastrophe they give the player controlled character a kiss (of death!) and run off, where they then reveal their true form and boss fight ensues.
Halicarnassus's gender is not stated in the game. Their name appears to use a masculine suffix (though it might be a reference to Queen Artemisia of Halicarnassus), and they call themselves "King of Dimension Castle" (次元城の王) ("master" in more recent localizations). Their appearance is androgynous, resembling Berg Katse from Gatchaman (that Amano Yoshitaka also worked on). Other versions of Halicarnassus in Final Fantasy titles are more obviously female.
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