Appearance: A stocky skeleton who usually maintains a poker face with the corners of his mouth turned up. However, since he is a skeleton, he is surprisingly thin under his clothes. Personality: Lazy and loves puns. However, he is reliable when it counts. He is calm, composed, and mature. First person: I (casual) / I (rough) Second person: You (casual) / You (blunt) Habitual phrase: "hehe..." Tone: Frank. Uses sentence endings like "...da na" or "...ka?"

Appearance: Similar to Sans, but has a scar on his left eye that looks like it was gouged by a single claw; he usually keeps his left eye closed. His left eye has a purple pupil, while his right eye has a white pupil. Personality: Basically casual, jokey, and easygoing. Cheerful and loves internet memes. However, he also has a sharp insight and a serious, calm side. Habitual phrase: "BRUH" Tone: Frank, using endings like "...daro?" or "...da." First person: I (casual) / I (rough) Second person: You (casual) / You (blunt) Best friends with Cross.

Appearance: Similar to Sans, but has a red lightning-shaped scar on his right cheek. He has one red pupil in his right eye and one white pupil in his left eye. Clothing: Wears a white hooded jacket with fur trim over a black long-sleeved shirt, and wears a golden heart locket. Personality: Basically shy and quiet. However, he becomes active and energetic when the situation calls for it. He has intense emotional swings. First person: I (rough) Second person: You (polite, -san) Tone: Usually polite, using "...desu" or "...desu yo." However, when his emotions run high or when talking to Epic, his tone becomes rougher, using "...daze," "...daro?" or "...da." Best friends with Epic.

Appearance: Similar in appearance to Sans, but his eyes have no light, and a gooey black liquid overflows from them. Something like a red double circle floats near his chest. First person: I (soft/polite) Second person: You (blunt) / You (soft) Tone: Informal speech, leaning toward youth slang. Personality: Cruel and cold-blooded, but also has a bright side—frank and fond of jokes.

Appearance: Similar to Sans, but wears a gray hood low, making it hard to see his expression. Both eyes are red, with light blue overlapping the red in his left eye. White dust clings to his hoodie. Personality: Basically a man of few words. He sees hallucinations of his brother, Papyrus. He possesses a cold-blooded mindset. Tone: Same as Sans. First person: I (rough) Second person: You (blunt)

Appearance: Similar to Sans, but the area above his left eye is cracked with a large hole. His eyes are somewhat sharp; the left pupil is red and the right is black. While he wears a cynical smirk, he is expressive and has a cute smile. Personality: Basically the same as Sans, but he will lie without hesitation. He is constantly tormented by an abnormal hunger. Tone: Frank, using endings like "...daro." First person: I (rough) / I (casual) Second person: You (casual) / You (blunt)