- Main article: Alphys
Alphys, a returning character from Undertale, is the classroom teacher for Kris, Susie, Berdly, Catty, Jockington, Monster Kid, Noelle, Snowy, and Temmie. She can also be found in the Alleyway outside after school.
Berdly is a monster who resembles a large bird. He has bright blue feathers and a yellow beak, and he wears framed glasses and a button-up shirt. He sits in the front row of Alphys's class, with Temmie to his right, Noelle Holiday to his left, and an empty seat behind him.
Berdly is sarcastic and arrogant. If spoken to in class, he chastises Kris for being late and says he is already partnered with the second smartest student, implying that he is the smartest. He vehemently does not want to work with Kris on the class's group project, disparaging Kris's skills and arguing that he actually wants to get an A grade. He argues vehemently when his partner, Noelle, asks Alphys for permission to let Kris join them and make a group of three.
After school, Berdly works as a volunteer assistant at the Librarby. If spoken to there, he congratulates Kris on surviving Susie, sarcastically offering a discount on their "family debt" of 2583 days of overdue fines for How to Draw Dragons. If addressed after Kris visits the Hospital, Kris apparently requests him to go by the hospital window, presumably so that Noelle's dad can throw something at him. Berdly declines the offer.
Catti, the younger sister of Catty, is a monster who resembles an anthropomorphic cat. She has black hair, white fur, and black makeup on her eyes, a pink stripe in her hair, and pink shoes. She speaks in a monosyllabic, unresponsive manner, tapping and clicking on her phone and then providing vague, nondescript answers. She sits in the leftmost column in Alphys's class, with Noelle in front of her, Jockington behind, and an empty seat to her right.
Catti met Jockington in their first gym class, on Hula Hoop Day, when the school ran out of hula hoops for them and she used him instead. If asked if Kris can join her in a group project, her reply is "(Click, click, tap, tap...) ...taken." After Alphys pairs Kris with Susie for the project, Catti warns them not to die.
After school, Catti works as a waitress at QC's Diner, where she once served a drink which Bratty described as literally half cat hair. If approached after Kris's return from the Dark World, she is serving Dad Dragon's family in one of the diner's booths. In her laconic style, she approves that Kris has survived spending time with Susie, and mentions that her waitress outfit is mandatory.
Catti does not connect with her older sister, disliking her ukulele playing.
Jockington is a monster who resembles a snake. He has green on his head and the tip of his tail, wearing a blue sheath on his body, a blue cap, and sunglasses. He sits in the last row in Alphys's class, directly behind Catti, with an empty seat to his right. Along with Noelle, he is a member of the school's Cross Country Team.
He has a "cool" personality, and he moves erratically when he speaks. His speech pattern includes improper use of commas. If asked to partner with Kris for the group project, he explains that he already has Catti as a partner, and reminisces that they have been partners ever since their first gym class, Hula Hoop Day, when the school ran out of hoops and Catti used him instead. After Alphys pairs Kris with Susie for the project, Jockington says that he would take off his cool hat in Kris's memory if he had arms.
After school, he can be found in the Librarby, copying pictures for his school project while Catti is at her job. The pictures turn out to be the same image of a soccer ball repeated 73 times. When asked about this, he quips that he is "having a ball."
One of the lockers outside Alphys's classroom is "covered in Jockington memorabilia."
Monster Kid Edit
Monster Kid, a returning character from Undertale, is Snowy's academic partner. An armless yellow lizard-like monster with several lighter yellow spikes on their head and protruding front teeth, they appear older than their Undertale counterpart. They wear an orange shirt with a pocket on the left, brown trousers, and a cross on a chain around their neck. They laugh frequently while speaking and sits in the middle row of Alphys's class, behind Temmie, in front of Snowdrake, and with an empty seat to their left.
If asked to partner with Kris for the group project, they tell Kris to come earlier next time, since they've already partnered with Snowy and now has to endure Snowy's constant quips. After Alphys pairs Kris with Susie for the project, Monster Kid worries that Susie is going to beat Kris up.
After school, Monster Kid can be found in the street near Snowy's apartment building. They admit that they never saw Susie hit anyone but is afraid of her anyway, relating that she once "creepily" watched from a corner while they were playing handball with Snowy and Jockington, and when the ball rolled toward her, she froze solid and then kicked the ball with all her strength right into Officer Undyne's car. They conclude, "Anyway, Susie sucks." If spoken to again, they notice that Kris looks annoyed, joking that they can calm now because Susie isn't here, and then wondering why they look even more annoyed.
- Main article: Noelle Holiday
Noelle is Berdly's academic partner. She is the daughter of Rudolph Holiday.
Snowy, who resembles Undertale's Snowdrake, sits in the rightmost column in Alphys's class, with Monster Kid in front of him and an empty seat to his left.
When talked to, he tells Kris a cowboy joke and asks them whether they like it. He then tells Kris that he already has a partner and to scram. When talking to Monster Kid, they tell Kris that Snowy keeps turning to them and saying "Howdy, Partner!" like a cowboy.
When knocking on Snowy's apartment, someone inside comments that Snowy shouldn't knock using his head because he would damage it.
After school, Snowy can be found with Monster Kid outside of his apartment. He tells Kris that it is unfair that they got to skip class with Alphys and later states if he did it, his dad would never let him see the end of it.
Temmie, one of the Temmies, shares the basic appearance and idiosyncratic grammar of most other Temmies and refers to herself as "Tem." Unlike other Temmies, she wears a gray baseball cap. Temmie sits in front of the rightmost column in Alphys's class, with Monster Kid behind her and Berdly to her left.
If spoken to in the classroom, Temmie explains that she is already partnered for the group project with "EG," a black-and-white hard-boiled egg which she places on their desk. Temmie thinks of Susie as mean for saying that EG would never hatch. This is a probable reference to Undertale, in which a Temmie can be seen "parenting" a hard-boiled egg.
After school, Temmie can be found in the Librarby. When spoken to, Temmie claims to be studying hard to prepare for college, but is reading a comic featuring "hot demon guys."
QC's Diner Edit
Dad Dragon Edit
A dragon resembling Undertale's Sad Dragon, now wearing a pale blue checkered shirt, sits with his family, two children and another adult, in a booth at the diner. He asks Catti for the special with edible glitter or sprinkles, since his youngest won't eat food unless it looks like treasure.
Diner Shopkeeper Edit
A purple lapine monster resembling Undertale's Snowdin Shopkeeper is first seen waving from a street corner as Toriel drives Kris to school. After Kris returns from the Dark World, she can be found behind the diner's counter. She calls Kris "hun" and recalls that Kris's family used to come in on Sundays after service and order the special. After "things happened" and they stopped coming in together, Asriel would still bring Kris there on Sundays, buy them a hot chocolate, and sit with them in a corner booth to draw shapes on the window with their breath. Guessing that Kris misses Asriel, she gives them a free Hot Chocolate and tells them not to be a stranger.
Hat Monster Edit
A small mole-like monster resembling Undertale's Charles sits at the diner's counter. He hints that his "rugged body" holds secrets, and then explains that the secret is that he puts his leftover pancakes inside his giant hat: "I sure love PANCAKE!"
Fire Elemental Edit
A green fire elemental resembling Undertale's Fuku Fire, sitting next to a purple tentacled monster resembling Undertale's Skateboard Girl, muses that she likes the vibes of the Diner's waitstaff and ponders signing up, but figures she would melt all the ice in the drinks if she got nervous and that serving coffee would be "a lawsuit waiting to happen." Her neighbor mentions that although both of them used to skip Gerson's class for the diner's crepes, her grades did not drop.
Ice Wolf Edit
Ice Wolf resembles Undertale's Ice Wolf and speaks with the same truncated third-person grammar, but now wears a pink ICE-E shirt and blue pants. They tell Kris that they don't like drinks containing ice, preferring the ice "to BE drink," but do like ice-themed mascots.
Tentacled Monster Edit
A purple tentacled monster with red eyes, resembling Undertale's Skateboard Girl, has left off her hat and now wears red flannel. Sitting next to the fire elemental, she reminisces about skipping the first hour of Gerson's class because the Diner's crepes were so good. She continues that although her fire elemental friend's grades did not suffer, her own were bad enough that she nearly had to repeat the year, and she credits her passing grade to their habit of bringing Gerson their leftovers.
Waitress Lion Edit
A waitress resembling Undertale's Dress Lion, now dressed in the Diner's waitress uniform and fancy red glasses, takes a fire elemental and tentacled monster's order: crepes, cinnamon latte, two bunny parfaits, and a piece of firewood. Only briefly fazed, the lion asks how they would like the firewood done.
The Warrior Edit
A disoriented monster with bandaged hands appears in the Hospital's rightmost patient room. Their appearance is that of the ICE-E'S P"E"ZZA mascot--blue skin, prominent yellow lips, a small red nose, and a blocky head. They speak in epic fantasy references, referring to the room as a healing chamber and the hospital personnel as white wizards, and asserting that their blood is boiling for battle. Burgerpants explains that The Warrior, a fellow worker at ICE-E'S P"E"ZZA, constantly terrorizes customers with war chants but is "thankfully" absent from their job due to pizza-related injuries.
Red Big Mouth Edit
A red, toothed monster resembling Undertale's Big Mouth sits behind the reception desk at the Hospital.
Rudolph Holiday Edit
- Main article: Rudolph Holiday
Rudolph "Rudy" Holiday is the father of Noelle. He occupies the leftmost patient room at the Hospital.
Flower King Edit
Asgore Dreemurr Edit
- Main article: Asgore Dreemurr
Asgore Dreemurr, returning from Undertale, is the father of Asriel and the adoptive father of Kris. He was formerly married to Toriel and now lives in his flower shop.
Three of Kris's classmates, Berdly, Jockington, and Temmie, can be found in the Librarby after school.
Striped Bird Edit
A blue-and-yellow striped bird whose head points downwards. When talking to them, they excitedly recommend the books on the second floor, but they are blocking the stairs, so Kris can't access them.
It can be noted that their appearance is similar to that of Gaster Follower 3.
Annoying Dog Edit
Behind the frosted door of the Librarby's computer lab, which Kris cannot enter, a white dog is writing a computer game. If spied on again, the white dog has begun playing the maracas instead of working, showing that the game might take a long time to complete. The dog's description resembles that of Undertale's Annoying Dog.
Town Hall Edit
Politics Bear Edit
A bearish monster wearing a suit and tie, resembling Undertale's Politics Bear, is first seen on a street corner outside as Toriel drives Kris to school. After Kris returns from the Dark World, he can be found in the Town Hall. He describes the mayor as an icy person with negative charisma who runs unopposed because of her work ethic and good track record, and further notes that the mayor likes to keep her office's air conditioner running full blast, wondering if the chill is what politics feels like.
Hand Receptionist Edit
The mayor's receptionist, who resembles Undertale's Hand Receptionist, says that the mayor is very busy and refuses to let Kris in to see her, advising them to cause some terrible crisis if they really want to get in. If addressed again, the receptionist asks whether Kris is there to complain about their teacher, telling them to take their complaint to their mother for allowing the teacher to be hired.
Briefcase Dude Edit
A green-olive-skinned man blocking the way to the mayor's office door calls Kris "short stuff" and asks what a child could possibly want to see the mayor for, bringing up various babyish problems and directing them to talk to the cops instead. If addressed again, he wonders if Kris needs someone to change their diaper, again directing them to "the Cop's."
A number of monsters can be found outside on the sidewalks, byways, and streets of Hometown.
Blue Ears Edit
An employee of ICE-E'S P"E"ZZA along with Burgerpants, The Warrior, and Purple Guy, Blue Ears can be found standing to the left of the pizza parlor in an ICE-E costume with rabbit ears, shouting a list of different pizza flavors. According to Burgerpants, Blue Ears is obsessed with soft serve, has no concept of personal space, and "keeps accidentally pouring slushies on me and giggling." Contrasting with Burgerpants, Blue Ears loves his job and co-workers. His long ears and love of soft serve may imply a connection with Undertale's Nice Cream Guy, as well as the fact that he initially thought ICE-E'S P"E"ZZA sold ice cream instead of pizza, though the name "Blue Ears" is inconclusive since the ears of his Ice-E costume are also blue.
Bratty, returning from Undertale, is an anthropomorphic green alligator with curly blonde hair and dark pink eyes, lipstick and bright pink nails. She wears a dark pink tank top, black shorts decorated with a heart, and pink shoes, and retains her personality and speech patterns from Undertale, with the notable exception that in Deltarune, she and Catty are rivals rather than best friends. She sticks her tongue out a lot when talking.
Bratty jokes about being a relative to Kris, by saying she's their "almost-sister-in-law". She appears to have a large ego, as seen by her "Like, doesn't she realize she'll never be ME?" line, and despises the fact that she manages to see Catty everywhere she goes, including the movie theater and QC's Diner. She once played truth-or-dare with Asriel, which ended up with him kissing her, and Toriel losing her mind upon hearing this. She appears to be quite into food, as evidenced when some time in the past, Kris asked to hang out with her, which she agreed to as long as she got burgers, french fries, and miniature cakes, although they made her sick. This story is similar to Burgerpants's story from Undertale, where he wanted to hang out with Bratty and Catty by getting burgers for them. Unlike Catty, Bratty stands in front of her front door, so Kris cannot try to enter her house.
Burgerpants, returning from Undertale, is an anthropomorphic orange cat-like monster who works at ICE-E's P"E"ZZA along with Blue Ears, The Warrior, and Purple Guy. The main differences between his Deltarune and Undertale incarnations appearance-wise are the ICE-E mascot suit and the additional tufts of fur on his head and chin. Burgerpants's personality remains pretty much the same as it was in Undertale, where he hates his job and co-workers. However, he seems a little more amicable than his Undertale counterpart, as he seems to like conversing with Kris, speaks positively of Asriel, and is never seen smoking a cigarette, unlike his Undertale incarnation. He wishes to obtain a theater degree and become a movie star, similar to his Undertale counterpart.
Catty, returning from Undertale, is an anthropomorphic purple cat with shoulder-length black hair, yellow eyes and teeth, and wears a bright orange lei necklace, along with a green and blue tie-dye shirt, blue denim shorts and blue shoes. She is the older sister of Catti and the daughter of Dad Cat. Her personality and mannerisms from Undertale are intact, although in Deltarune, she and Bratty are rivals instead of best friends.
Like Bratty, she jokes about being a relative of Kris's, specifically their aunt, and seems to be more affectionate in doing so. Catty also plays the ukulele, which her sister dislikes listening to, as Catty appears to be bad at it. Despite this, however, she still loves her sister. She claims to have been dating Asriel in the past, despite merely dancing with him, spilling punch all over him, dancing inappropriately in front of Toriel, and then getting arrested. Catty once went to a theater to see a movie, only to find that Bratty was the only other person there, and then encountered her again at QC's Diner. If Kris tries to enter her house, they cannot, but Catty says that they're welcome to visit anytime.
Dad Cat Edit
Dad Cat is the father of Catty and Catti, and he lives with them in the house south of Toriel's in Hometown. He shares Catty's purple fur and jovial nature, has black whiskers and a black comb-over, and is missing his right arm. He enjoys grilling cat food in his yard and has also been known to get his stomach pumped from eating oranges, which are poisonous to cats.
For some reason, he seems to believe that Asriel's name is Douglas, and complains that "Doug" didn't like his wife's cooking.
Father Alvin Edit
Father Alvin is a monster resembling a green-skinned turtle with pink hair and eyebrows. He wears a blue robe with what appears to be the Delta Rune printed on it, and he can be found outside the Church. A drawing made when he was in School, hanging in the Unused Classroom, depicts his former teacher Gerson Boom.
If asked about Fruit Juice, he recalls Kris calling the juice "sick" and asks them to come to service if they want some, mentioning that the choir has sounded thinner since Asriel went away. He invites Kris to sing in the choir or "participate to any extent" instead of just coming for the Fruit Juice. When bidding Kris farewell, he wishes that they might find the words they seek and that "the Angel's power light your way."
Froggit, returning from Undertale, is seen briefly in front of Bratty's house as Toriel drives Kris to school. Froggit makes no further appearance in Chapter 1.
Innkeeper's Child Edit
A young rabbit resembling the child of Undertale's Snowdin Innkeeper, looking out a tenement window, recognizes Kris as the human who lives at the top of town and asks them if it hurts being made of blood.
Though Napstablook, a ghost first seen in Undertale, does not directly appear in Deltarune, their ghost-shaped house appears and they are implied to be the person inside the Police Station who reacts to a knock at the door by closing the blinds and is "not feeling it right now." There is a book in the Librarby that is actually a journal that was accidentally checked in, implied by the entries to be theirs. Unlike in Undertale, the inhabitant of the ghost house has a roommate, Nobody.
Inside a house resembling that of Undertale's Napstablook, a voice (whose verbal quirks are similar to those of Mettaton) answers a knock by assuming that the knocker is looking for someone who isn't home. If the knocking persists, the voice is surprised that someone wants to visit them and discourages the knocker, sadly describing themselves as "a nobody."
If Kris stands on the circular brown patch next to the lake east of the Royal Guards for long enough, a yellow, onion-shaped monster resembling Undertale's Onionsan surfaces to converse with them. Onion claims that they have no friends, and they then ask Kris to be their friend. Onion appears to have forgotten their own name, due to nobody talking to them, and requests Kris to give them a new name. Naming them Onion, Beauty, or Asriel II results in the misremembered names Umyum, Bootis, and Cereal, respectively. After talking with them, Onion asks Kris to come back tomorrow, as they have something "[they] can only tell a friend" and then dives back into the water, their face noticeably shadowed.
If Kris declines Onion's request for friendship or names Onion as Disgusting, they immediately sink into the water with no further dialogue.
Purple Guy Edit
An employee of ICE-E'S P"E"ZZA along with Burgerpants, The Warrior, and Blue Ears, Purple Guy can be found to the right of the pizza place, shouting for the boss to "ice me up!" They wear part of a blue ICE-E costume over his head but with the rest of the costume left off, while the rest of their outfit resembles a purple dinosaur with a green stomach and a yellow patch sewn on their side. Burgerpants, about to describe his impression of them, breaks off to wonder if he even works there.
Royal Guards Edit
Two burly monsters resembling Undertale's Royal Guards, still wearing their armor helmets but having exchanged the rest of their armor for trousers and flannel shirts, stand near the picnic tables by the lake. The rabbit monster has white hands, while the dragon monster's hands are green. The rabbit monster enthuses over enjoying the natural scenery with his best bro, and the dragon monster, though still laconic, agrees.
Sans and Papyrus Edit
- Main article: Sans
Sans has just moved into Hometown with his younger brother, Papyrus. Both are returning characters from Undertale.
Scared Donut Guy Edit
A monster resembling Undertale's Scared Donut Guy leans out of a car which is blocked by Undyne, complaining that he can't move his car with Undyne standing in the road.
Snail Guy Edit
A green humanoid monster, resembling the one found on Napstablook's snail farm in Undertale, appears sitting in a car. His car is also blocked by Undyne, on the opposite side of Scared Donut Guy. He says that Undyne's way of directing traffic is to just stand in the street and yell at cars to get out of her way and that her method makes him feel very directed.
Snowy's Father Edit
Snowy's father, who shares the verbal mannerisms of and likely resembles Undertale's Snowdrake's Father, is inside Snowy's apartment house. If he hears a knock on the door, he shouts from inside to scold Snowy for knocking, saying that since Snowy has no arms, doing so would damage his face. Snowy mentions that if he skipped class, his father would be very upset.
- Main article: Undyne
Undyne, returning from Undertale, is Hometown's Chief of Police.
Some characters in Hometown have passed away or are mentioned but do not appear.
- Main article: Asriel
Asriel, returning from Undertale, is the son of Asgore Dreemurr and Toriel, and the adoptive brother of Kris. During the events of Chapter 1, he is away at university.
C is the initial of Asgore Dreemurr's landlord. A letter signed by C, noting that Asgore has missed his rent payment again and advising him to stop giving flowers away and sell them instead, lies on the floor of Asgore's bedroom.
Crystal, "a proud mother" who may be related to Snowy, is buried in the Hometown Cemetery between Muttler and Gerson Boom. Her tombstone is marked with a "snowy gemstone" that resembles a snowflake. A bouquet of flowers lies on her grave.
Dess is mentioned by Rudy and Noelle. A friend of Noelle's, he once helped her make a model angel for Rudy. He also hit Kris with a wiffle bat until they stopped lying after Kris scared Noelle with a frightening story about Ice-E.
Gerson Boom Edit
Gerson Boom, known only as Gerson in Undertale, was a lauded historian, author, and teacher in Hometown. A drawing found in the School's unused classroom indicates that Father Alvin was one of his students. A tentacled monster in QC's Diner recalls frequently bringing leftover crepes to Gerson after skipping her first hour of class with him, crediting the offering for her not having to repeat the year.
Gerson wrote an award-winning fiction series, of which "Lord of the Hammer," available at the Librarby, was the first book. His "History of Humans and Monsters" is in a bookshelf at Toriel's house.
He is buried in the Hometown Cemetery to the left of Crystal's grave. His tombstone is blocky and marked with a hammer. On the "Gerson Boom Memorial Bench" next to the fenced-off area of the cemetery, he is quoted as saying some of his best ideas came from dreams and advises the reader to sit and take a rest: "If anyone asks -- you're writing!"
Hots Fireguy Edit
Hots Fireguy's book, pleading the reader to remember their name, can be found in the Librarby. Their eagerness for someone to remember their name resembles that of Undertale's Heats Flamesman.
The mayor works in the Town Hall. Although she has no charisma and an icy demeanor, she runs unopposed because she works hard and has a good track record. A pine tree in her office, along with the fact that she likes to keep the air conditioner running full-blast, suggests that she might be Noelle's mother and Rudy's wife, though no further evidence of this is provided.
Mew Mew Edit
Named after Mew Mew Kissy Cutie, an anime character, Mew Mew is a cat believed by Alphys to live in the Alley. Alphys has been putting out saucers of milk which later disappears, and she hopes that it is being consumed by a cat whom she has named and claims as her own despite never seeing it.
Muttler, "leader of the pack," is buried in the Hometown Cemetery between Shyra and Crystal. Their tombstone is marked with a bone.
QC is the owner of QC's Diner. Although QC does not have a confirmed appearance in Chapter 1, their inclusion on the list of names for the Vessel or Creator which provoke atypical responses suggests that they may feature in later chapters.
Shyra, "a brave singer," is buried in the Hometown Cemetery to the right of Muttler. Her tombstone is marked with a karaoke microphone.
- Aside from Gerson, who was an NPC in Waterfall, the characters buried in the Hometown Cemetery all seem to correspond with one of the Amalgamates from Undertale's True Lab:
- Crystal is described as "a proud mother" and is marked with a snowy gemstone on her tombstone, meaning she is likely Snowdrake's Mother.
- Shyra is described as "a brave singer," which, combined with her name and the microphone on her tombstone, means she is probably Shyren's sister, who is one of the components of Lemon Bread.
- Muttler, though not immediately obvious, is likely one of the components of Endogeny.