Killer sans is from Something New. He's a skeleton that has gotten completely emotionless due to his experiences from his past. He rarely eats due to him relapsing and causing him to feel guilt. He got recruited by Nightmare sans from an ending from Something New, and he's the first member in the Bad sanses. He also attempted to flirt with nightmare once, since he's quite romantic. He likes also likes cats and seemed to own one for a while. He can also speak in arabic like his creator.