It's guardian of negative emotions, brother of female dream sans and she hates her. She is octopus, she is goopy also he is more powerful when he feel more negative emotions. She e can attack you with goopy bones and with tentacle, use his tentacle to grab you and shake you, he can summon nightmare papyrus. She also have minion mamed killer. She uses her abilities when you fight her or she fights you. It's nightmare!sans but that's female. She is rude.