Board Thread:General Discussion/@comment-6986530-20171111052140/@comment-2602:301:77AD:9270:65D6:1485:A2EB:97B4-20171128162812

It could have just as easily been the other way around. It was explicitly stated when Elluka was reincarnating them that they could become male too, so it could have been Gumillia going from one sex to genderless to the opposite. What they were in their Second Period incarnation has no impact on what they could reincarnate as after becoming spirits (which was the original point of this comment thread, the above anon wondering about the logistics as gender has been a reincarnation barrier in the past). The case is unique by coincendence, not design.

What it implies or doesn't imply is a conversation for later, but this is just the point I was making.