Merfolk (males are called mermen, and females are called mermaids) are aquatic humanoids that thrive in the coastlines. They are usually revered and awed for their unnatural beauty and pure hearts, although some have grown a strong hatred for land humanoids (called "surface-folk" to the merfolk) for several reasons, including unnecessary genocide and competition for fishing grounds.
Merfolk of both genders usually assume the physical attributes of humans of the same age, even though merfolk generally live as long as elves and djinns (there is a legend in merfolk society that one queen lived for almost 100,000 years, although no evidence exists for a mermaid living even half that long; a more likely age would be 2,000 years). Merfolk have gill-like extensions on the sides of their necks, elven-like ears and human-like eyes. Their lower bodies generally have the shape of a eel or sea serpent with a fluke similar to a dolphin or whale. Mermen usually grow a beard that shares the same color as the hair on thier heads starting at the age of 40, but once they reach the age of 75 the beards generally grey out. Merfolk enter puberty at the same age as humans, but puberty usually ends at the age of 15 to 17 years old. Mermaids usually have long hair that can be as long as their bodies.
It is unknown when the first merfolk societies and civilizations first appeared, but, according to those merfolk who could reveal as much as they know about their history, merfolk civilization appeared about 600 years after the Great Dawn (the time period when several humanoid societies and civilizations appeared simultaniously). They used to be great allies with the caecellia, the half human, half octopi humanoids that were skilled at magic, something the merfolk lacked. However, when the caecellia turned to dark, necromatic magic about 150 years later, the merfolk were warry, thinking that the dark magic will destroy their society. Fortunately, they were able to discover that the caecellia have also gave their souls to abyssal demons, and, as a result, they were either killed or exiled by the merfolk.