Imagine if you will:
A drow soldier of commoner stock.
He his big and strong for a drow, but not smart enough to apply to be a wizard.
Due to in-house politics or simply because the house Breeding Mistress picks him out for virility, he is commanded to breed the hobgoblin slave women.
No drow woman, no matter how lowly would be subjected to the indignity of bearing the offspring of a lesser race, of course.
Thus it falls on the hand picked drow males to provide the neccessary seed.
Our drow protagonist is forced, at whip-point, and possibly fortified with several doses of potions of endurance and "potency", to spend night after night fucking the biggest, strongest hobgoblin females, knocking them up to provide elite slave troops for his House.
Since no drow women would want him anymore, after this degrading task, he must resign himself to a life as a breeding stud and to train his own offspring to be warriors, for decade after decade.
Maybe that's something you could work with?