First person: Boku, Ore Second person: Kimi A member of the Star Sanses. Personality: A prankster, childish, energetic, and kind. High-tension and cheerful. Since he has no emotions, he supplements them with colored ink from small vials. Age: Unknown Male

First person: Ore Second person: Omae A member of the Star Sanses. Personality: Ruthless and aggressive, but in reality, he is extremely exhausted and still harbors some sentimentality deep down. Likes mustard. Likes Sans. Age: Unknown Male

First person: Ore Second person: Omae A member of the Bad Sanses. Personality: Loves massacres; ruthless, aggressive, and psychotically energetic, but not kind. Characterized by a mad laugh. Occasionally calls Nightmare a "tentacle-octopus." Age: Unknown Male

First person: Ore Second person: Omae, Kisama The Emperor of the Bad Sanses. Personality: Hates positive emotions and enjoys seeing the despair and suffering of others. Has a younger brother, Dream Sans, whom he hates. Has four tentacles growing from his back. Gets angry when called an octopus. Age: 502 Male

First person: Oira, Ore Second person: Omae, Omaesan, Anta Wandered into this place (Underverse). Personality: Laid-back, works at his own pace, and lazy. Loves cracking jokes, but behind that, he is a genius who understands the mechanics of the world. Likes ketchup. He is exasperated by Fell constantly clinging to him. Age: Unknown Male

First person: Ore Second person: Omae Working hard to defeat X-Chara and Gaster. Personality: Serious and kind. Possesses a strong will to protect loved ones and others, though he hasn't fully awakened to that heart yet. Age: Unknown Male

First person: Boku Second person: Kimi, Omae Hates X-Gaster. Personality: Actually kind; doesn't do things because they want to, but because they are being threatened. Possesses a strong will and pure love, but currently acts like a cold psychopath. Ruthless and feels beyond help. Can swap forms with Cross. Age: Unknown Male

First person: Boku Second person: Kimi Nightmare's younger brother. Personality: Positive, kind, energetic, and bright. Never stops smiling. Intends to stop X-Gaster, Chara, and Nightmare. Guardian of Positivity. Age: 502 Male

First person: Watashi Second person: Kimi, or by name if an acquaintance. Used X-Chara as a test subject. Personality: A ruthless personality that treats death and sacrifice as matters of course. Always calm. A psychopath. Steals SOULs. Age: Unknown Male

First person: Ore Second person: Omae Has haphephobia (fear of touch) because he glitches when touched. Personality: Hates noisy or colorful places. Enjoys the despair of others. The God of Destruction. Always in a bad mood. A member of the Bad Sanses. Enjoys knitting. Age: Unknown Male Likes chocolate. Occasionally calls Nightmare an octopus.