Futanari of the Apocalypse

Futa on Male Nuclear War has left the world in ruins. Most of the survivors have turned into flesh-eating zombies from radiation. Survival is an ongoing battle, and by some miracle you have been able to make it this far--mostly by running away and cowering in fear while living off of the scraps you come by. However, one fateful day would see your fate change entirely as you encounter two very capable goddesses.