Half the height of a Human, the males tend to be very ugly rude and violent, and the females tend to be very sweet and pretty. Goblins are susceptible to suffocation by a fog produced by the naga, a species they share underground territory with.
During the Harpy Goblin war, the Harpies cursed the Goblin girls to only like ugly violent men, so by natural selection all of the decent men disappeared. The curse was abated later, but by then the damage was already done.
- Heaven Cent, Chapter 10