She said "male empty man" so I'm guessing they can be female too?
It's someone who can produce strong children by filtering out weaker genes, assuring that stronger fenes will be passee on.
Like in a previous chapter the grandparents said that the powers Gala have hasn't been seen in centuries. Gala was able to get those powers because Yunshen is an empty man so when he was carrying the twins, the strongest genes he was carrying were selected. Weaker genes that block those powers from manifesting were filtered out.
Trolese thinks Yunshen doesn't know hos true identit as an empty man. Idk why he said that but maybe it might be that it wasn't explained to Yunshen well enough so he doesn't truly understand how valuable he and his kids are.
Uhhh can someone explain to me wat is an 'empty man' again. I'm a little confused on dat part