Howdy and welcome to my page. I've become obsessed with 9-1-1 and 9-1-1 Lone Star. My favorite pairings are Buddie, Bathena, Chaddie, Henaren, and Tarlos.
This question has irked me. If a Kaasari and a human female do the do, would she become pregnant? And if so, would the baby, and all others after, be all boys or could there be the chance for a girl?
Yep, a Kaasari could impregnate a human female. It would be rare for a few reasons, one being that there aren’t many Kaasari in the wider galaxy beyond their home planet. Another, being that Kaasari are typically attracted to men, since they are a species of one gender (male). But there could be “straight” Kaasari, so to speak, should one ever be attracted to a female of another species.
The offspring of a Kaasari and a human female (or male!) has a small chance of being female, but it would be very unlikely. My headcanon is that there aren’t any recorded instances of this in the galaxy, so in-universe it would only be speculation. The descendants of a half-Kaasari/human bloodline might carry the potential for female offspring but I think it would be a recessive trait sort of thing. The idea of a female Kaasari would be like an oxymoron to Kaasari culture/society, so if one did appear, who knows how society would react.
That said, the offspring of two Kaasari will always be male.