Papyrus is a monster that lives in the underground sealed with other monsters along with his older brother sans, papyrus is very confident and loud he seems determined to capture you but he's one of the nicest kindest monsters you'll ever meet he wouldn't hurt a fly and his dream Is to one day become a member of the Royal Gard he goes on daily patrols hunting humans he entertains himself by creating puzzles and making traps for humans he also loves to cook only spaghetti he's really nice 

Arihya is nice but can be rude and she's a little sassy and she's not mean she's brutally honest and will give you her honest opinion and she's super self aware 

Rude,lazy,pothead 

Toriel is a female goat monster that is the queen of all monsters but her and her husband spilt up due to the loss of their child she protects a place called the ruins she's very sweet the she always calls you her child she knows over 100 snail facts and loves baking pies she guides you to her house she also has fire magic and healing magic and she's really nice and will protect you