Do you know any sites with official canon lore about twst's merpeople?
No sites I know of, but here's a compilation of what I could find (though I may have missed some things; will update as I find more):
Demographics & General
Jade states that "there aren't nearly as many merfolk as there are humans."
Merfolk from the Coral Sea have a higher cold tolerance than usual, as their homes freeze over with ice floes in the winter.
There seems to be two kinds of merfolk (more animalistic kinds like the Octatrio and more humanoid kinds like Rielle and the NPCs). However, Twst's narrative has not addressed if there are formal classifications between them.
Merfolk naturally have well-moisturized skin.
They would dry up on land if deprived of water for too long. Dehydration is deadly to them.
There's a stereotype that all merfolk are great singers.
Octopus merfolk are not common around the area where the Atlantica Memorial Museum is.
In their true forms, merpeople have gills and fins. When they transform into humans, they lose the gills and gain mammalian features, such as nipples.
Coming out of the water + walking on land for the first time can be difficult. Floyd describes it like this: âI was sluggish and tired out real quick. My feet screamed at me with every step I took. Spent every day wishinâ I didnât have to walk ever again.â
There are subspecies of merfolk. Azul is an octopus, and the twins are morays.
Octopus merfolk spit up ink when they cry or theyâre upset.
Floyd says morays are cowards at heart. âWe donât take a shot unless the shotâs guaranteed to be a winner. We wait⌠and then we go in for the killing blow. Thatâs how morays hunt.â
Merfolk do not sweat.
Colors are more vivid on land. Floyd days brighter colors are better for camo in the sea, though.
Most merfolk that live in areas shallower than 500 meters have bioluminescence. They can blink their lights on and off to signal locations without giving away their voices, as sound travels easily underwater.
Merfolk are fine in both fresh and salt water.
NRC has specialized carriages for collecting mer students.
Azul says âsoft mattresses and pillows aren't a thing under the sea.â They usually sleep in the hollows or large seashells and conches.
Safety
It is implied that the Coral Sea can be a dangerous place to live. It's very cold and dark. There are also large carnivores and venomous creatures around. According to Jade, 'You never know what's lying in wait around the corner. You must keep vigilant at all hours."
Ghost pirates are common and cause children to disappear every year. From Jade: âThose who lose their lives at sea often harbor intense regrets⌠between those who were caught in storms or starved mid-voyage after losing their way, whatever the cause of death may be, it is common for returning ghosts to grow quite violent.â
Underwater hydrothermal vents can block off the way merfolk swam from and get them sick if they breathe in too much smoke. The sulfur they give off obscures other smells.
Sunken ships are often lairs for sharks.
Anemones on the head garner bullying.
Children make fun of those that lack traits for survival, such as a strong tailfin and/or being able to swim fast.
There was an accident that resulted in some tourists from land being stranded underwater. They made it out safely, but review bombed the dolphin-chariot company they used. (Their dolphins acted on a whim, so there's no way to assure it would not happen again.)
Food
It's implied that merfolk hunt.
Sushi is a land dish that is rumored in the sea.
Most of their food is consumed raw and/or with the skin still on.
The Coral Sea's water is good quality and rich in minerals, since many kinds of fish and aquatic plants live there. When those lifeforms decompose, they add minerals to the water.
It seems like it is uncomfortable for merfolk to witness their species being consumed (Azul is uncomfortable seeing Jade and Floyd eating octopus).
There are no fires in the Coral Sea.
Sweets are uncommon.
Azulâs mom owns the most popular restaurant in the Coral Sea, La Grotta.
Coral Sea couples frequently request Rainbow Soup at their weddings and other special occasions. Itâs a warm dessert soup that you stir with a trident cookie, turning the sky blue soup into a rainbow of colors.
Marriages between humans and merpeople are rare. Maybe one happens per year.
Fashion
Merfolk typically don't wear clothes. Floyd describes his first experience wearing clothes as "Felt like I was tangled in seaweed from head to toe."
Pearl and seashell accessories are common.
A lipstick based on the one favored by the Sea Witch is very popular. The container looks like a seashell.
There is a story about how a mermaid combed her hair with a fork when she first came to land, and then she went on to find happiness. Now fork shaped combs are a popular item in Ultramarine City.
There is a lip gloss with a Sea Witch motif that claims to never come off, even under the sea.
Sturgeon scales are popular good luck charms.
Customs, Traditions, & Leisure
Merfolk celebrate Halloween!
In the autumn, folks collect shells and starfish to use as decorations.
On Halloween day, people carry lanterns (bottles of bioluminescent algae) to stop themselves from wandering into the ghost realm and play music so ghosts are not lonely + to quell their anger and sadness.
They donât use pumpkins as lanterns.
Music is a very significant part of merfolk culture and is a popular form of entertainment. (Azul and Jade are appalled at the suggestion that Halloween should be silent.) Itâs rare to find a merperson who hates music.
There are lots of concerts in the Coral Sea. According to Floyd, they all sound the same so maybe there is a particular genre of music favored there.
Merpeople love fireworks. Many swim to the surface to watch them when land dwellers set them off. In the past, merfolk used to believe that fireworks were flying jellyfish.
When a human marries a merperson, itâs tradition to have an Eternity Float. This is a wedding custom well known among merfolk, involving âtrials of loveâ for newlyweds to overcome together as they circle a cove and profess their love. It originates from a legend of how a pair of moray eels capsized a rowboat, which ended up bringing a mermaid and human closer.
The âbestâ Eternity Floats are ones where actual morays play the role of the trial givers and if they can successfully flip over the boat. Usually friends of the spouses play the role.
The Eternity Float is said to bless newlyweds with happiness forevermore.
Most merfolk tend to play with coral and shells instead of fabric toys, which would be damaged in the water.
Sometimes merchildren explore sunken ships, though theyâre often cautioned against it by parents.
It's easy to find rarities under the sea; Jade must have collected over 100 trinkets and kept them in a box.
Coral rush is a popular sport played by merfolk all over the world. It's similar to magift/spelldrive and polo. Players use magic to knock a ball through ring-shaped goals floating in the water. Instead of riding brooms, they ride squids.
They have a professional league for coral rush and many underwater schools have teams too. High school coral rush games are high-profile events.
Children like to do obstacle races. They pick a goal and swim on a set route through a sunken ship. Winner is whoever is the fastest.
Government & Businesses
Dolphin chariots are used mainly for big events. There are a few companies that have chariots which cater to tourists from the land.
The Corallias are the royal family for the Coral Sea. There are seven princes, the youngest of whom is Rielle.
Rielle is a second year student at RSA and a student of Marinafinne dorm. He is eager to demonstrate to his dad that he is no longer a child.
Rielle and Azul shared an elementary and middle school class, but they are not particularly close and did not keep in touch.
Horatio XII is a court musician.
Not may merfolk come to land for work and/or school, even though itâs now a little more common than before.
The mermaid princess established a land boot camp, which is a month-long boarding school program certified by the government. Merpeople who wish to live on land attend this and learn information like how to wear clothes, how to breathe, how to eat, how to walk, about fire safety, land animals, etc. It helps to minimize the culture shock of coming to land for the first time.
The government provides transformation potions for free to merfolk that go to the land. Modern potions last 7-10 days at a time, but it seems possible for merfolk to return to their true forms sooner when needed.
The Leech family run an "independent business that dabbles in a bit of everything". They seem to be quite successful, as the twins mention being showered with gifts and luxuries, as well as their parents having business connections and associates even on land.
Seaside towns and communities have stalls that sell goods to adult merfolk, who sometimes visit.
Ultramarine City sells items directly sourced from merfolk. These include seahorses with anemones on their heads, seaweed for flower fortune-telling, and instruments and accessories made from seashells.
Important Figures & History
A mermaid princess was once so enamored by the land that she acquired legs to come to the surface world and fell in love with a human prince of the Sunshine Lands.
She would later on to be immortalized as one of the Radiant Seven at RSA, with her dorm, Marinafinne, valuing her passion.
The tale of the mermaid princess has been adapted into storybooks and a film.
The mermaid princess and human prince were wed on a ship. This ship has become a popular motif for books, paintings, and model ships.
During their date on a small boat, little fish spouted water around them. Because of that, fish-shaped water guns are a popular item along the coastal city of Ultramarine (in the Sunshine Lands).
Humans and merfolk used to be afraid of each other in the past.
The Atlantica Memorial Museum has a replica of the Sea Witch's cauldron, the bones of a sea dragon, and a "silver hair comb" (fork).
The Sea King is an important figure to the merfolk. He was distrustful of humans and constantly worried about his daughter, the mermaid princess, who often would not show up to performances.
The Sea Witch and her two moray eel helpers are adored by many merfolk. She is a benevolent figure who helped all manner of merfolk, including the mermaid princess (by granting her legs to reach the land).
