Going off what I know about cats and gender (unrelated subjects), I get the impression that Nunh might actually qualify as a third gender in Seeker society. Well...I guess the asexual Tia might be the third gender, with them becoming traditionally "male" under specific circumstances, triggering actual hormonal changes in the former Tia. I think this may be related to the intensity of feline estrous, which would wreak havoc in a sentient species unless there were social constructs in place to adapt to it.
Given that Seeker biology and society seems very similar to African lions, this led me to wonder if it was possible that a Nunh might be female. There's a phenomenon among African lions wherein females in prides without males will actually grow manes and adopt the male lion's role. Similarly, in a tribe without any males (Tia or Nunh) might a female undergo similar hormonal changes and adopt the role of Nunh?