2 princesses is pretty much a necessity to fight off the armies that follow.
You might get away with bird princess + ashes, but that's boring and would probably end painfully a few times.
I'd go for slime + trap. Slime because I think slime girls are qt and trap to get lewd with. The combined armies of the trap and the slime, as well as the trap earning the allegiance of the human kingdoms, should be enough to fight off the backlash from the other kingdoms too.
>>587Looks like you're stuck with the bird princess then.