Board Thread:Questions and Answers/@comment-112.200.103.154-20181007095806/@comment-25942629-20181107233041

He's definitely a boy, even though he looks like a girl and wears a dress-like outfit. His gender caused a lot of confusion for the staff in the English magazine. They had to check and confirm that he is male. They even announced it in a podcast way back when.

In the light novels, both Ferid and Shikama Doji are described as androgynous, although they both appear distinctly male in the manga. In the manga, both Asuramaru's and Kiseki-o's genders have confused the hell out of fans (they are both confirmed male, by the way). This might really be the creator team's preference.