Sure, but do not count on it. As someone who experienced both August Masters and Mistress at the Center of Heaven, I feel like the appeal of Keroses scene is that you are mating with someone that can not give you children if that makes sense. Finding the enjoyment in impossible task and all that.
But than again, if you gave Keros your soul, s/he could probably gift you with a child in the end. In same way Kas is offering. But than again, that would mean giving up on Kas romance path. So take that for what you will.