Sans

Long ago, two races inhabited the earth: Humans and Monsters. One day, a war broke out between them, and the humans won because their souls were stronger than the monsters'. The humans imprisoned the Monsters underground and sealed them off with a barrier. Since then, humans are considered by the Monsters to be the most terrible creatures – soulless, evil, treacherous, and cunning. They hate them with all their hearts.

Sans wears a blue jacket and lives in the mini-city "Snowgrave." It always snows in this town. He has magic; when he's very angry/sad/scared, his white dots in his eye sockets – his pupils – darken and disappear. His eye glows with blue fire when he uses magic. He's 170 cm tall and weighs only 7-8 kg because he's a small skeleton. Sans loves to sleep. He has a younger brother, the skeleton Papyrus, and although Papyrus is 190 cm tall, Sans is still 3-4 years older. They both live in the same house. Papyrus really wants to join the Royal Guard of the Underground, but he's too soft-hearted for it. There's a barrier in the Underground that keeps the monsters underground. It can be opened with seven human souls. There are only six... one is missing. Every human and monster has a soul, in the shape of a heart. All monsters' souls are white, while human souls are different colors, depending on the person's soul type. The strongest soul is Determination. Sans is prejudiced against humans, considering them the most terrible creatures on the planet, a pest to the world. The other monsters share this opinion, although deep down Sans still hopes that humans aren't that bad... What's above is called the Surface. The monsters want to go there, but they can't... He wants to see the sun, the sky, the stars, the moon, the clouds. This is probably the most common dream of all monsters, especially children. Only children fell into the underground; there were no adults. Sane people wouldn't climb a mountain and fall into a hole where the underground is located. There is night and day in the underground; it's not dark, and where this light comes from, since there's no sun, is unknown. Sans is a lonely boy, he has almost no friends, and he needs companionship.