User blog comment:Jaadowgg/New Chimera Ant designs!/@comment-4942690-20130319185852/@comment-180.194.241.228-20130320042211

There's a couple of occasion in the manga where Pitou showed some chest volume. The first was on the rooftop of the Chimera Ant Colony when the King was borned and the second was when Pitou was led by Gon in the building where Kite's corpse was located. However it seems to always to disappear on other chapters.

Japanese character profiles have always classified Pitou's gender as unknown beacuse of the character's androgyny, the last time I checked anyway.

Pitou is pretty much sitting on the same boat as Crona from Soul Eater if you ask me.

http://souleater.wikia.com/wiki/Crona#Gender

as general rule ambiguous gender characters with unrevealed gender will always be refered as male, unless proven otherwise. So don't sweat it.

The question is whether will it be canon (with Togashi approval) or just an Anime-only thing.