Kris is a human teenager with an amber skin tone and shoulder-length dark maroon hair with long bangs. They wear a long-sleeve lime shirt with one horizontal yellow stripe,and have red eyes that can glow in the dark, In the Dark World, Kris's entire appearance transforms, making them resemble a knight. Kris dons silver armor: shoulder pauldrons, a cuirass, gauntlets, and boots.

Susie appears as a Dinosaur Monster. She has yellow eyes with black pupils. Her scaled skin is purple. She has long dark purple hair, and clawed hands,For clothing, Susie typically wears tomboyish clothes. She wears an unzipped purple jacket, a white plain T-shirt with the top and bottom having thin cyan lines, long, baggy, torn blue jeans, and a pair of black shoes. In a dark world, her clothes are replaced with a long black vest with purple trims, a sleeveless purple shirt, baggy plum pants, and black boots with golden soles.

Ralsei is depicted as a short Darkner who is friends with Kris and Susie but Darkeners can't go to the light world,so often Kris and Susie go to visit him. He initially wears a hooded, dark blue cloak which obscures his face,later he is revealed to be strikingly similar to a younger goat Monster, though he has pink horns. He also has new black sleeves, and has healing powers.

Berdly is a lightner who resembles a large avian with blue feathers, a yellow beak, and yellow legs. He wears black framed glasses, a collared white button-up shirt with striped sleeves, and a black shirt layered underneath, In the Dark World, Berdly's feathers are a lighter shade of blue, and the whites of his eyes are bright green. He wears a "Smart Scouter" on his head that consists of an orange tinted lens and two white and green pointed headsets.

Noelle appears as an lightner anthropomorphic reindeer with short brown fur, a red nose, two brown antlers, and two fluffy deer ears. She's quite thin and small. Her eyes are big and have black pupils, on her eyes, Her clothing consists of a bright green and red vest, a white collared shirt underneath her vest, black sleeves, a black skirt, In the Dark World, she only wears a long white robe with wide ample sleeves.

Queen is a darknerr tall and slim black, azure, and white Darkner. She wears a sleeveless black top with an azure masonic collar that has slightly spiked shoulders and a large white medici-styled collar, Queen is a somewhat benevolent, if airheaded, figure. While she is prone to forcibly controlling and oppressing her subjects.

Tenna appears as a Darkneer humanoid figure with an old TV for a head, lacking any facial features aside from a wide, often-grinning mouth and a long, pointed nose, However, after years of no longer being used by his owners (he was simply a TV before getting a body, he's become determined to try and keep an audience no matter what, tenna is an upbeat and energetic show host who thrives on entertaining his audience by both flattering and challenging his contestants.

Alphys appears to try her best in guiding her students to succeed. Alphys is implied to be a recluse, often eating instant ramen noodles in the dark when she is at home, alphys is a yellow lizard-like monster with buck teeth. She wears square glasses, a dark green jacket, a red tie, a light green shirt, and brown pants.

the Knight's appearance seems amorphous in nature, their "resting" form possesses long limbs, pointed legs, jagged shoulder protrusions, and what appear to be holes in their hands,no one knows it's real wants or plans,or even it's identity, because it's real identity is another character,and no one knows who it is,the only know thing is that it is a darkner.