Jessica Grey is one of the antagonists of Season 2, before becoming a main protagonist in Do or Die. She's the director of the Anti-Monsters Department (AMD). She made her first appearance, as a cameo, in Continue, then an official appearance in My Sunshine.
Appearance
Jessica is a middle-aged woman who wears a short blue dress that ends above her knees. She is shown to be much taller than Frisk, but shorter than Papyrus and Gaster. Her hair is primarily black, with a certain portion being gray. Over the course of the season, it transitions back and forth between gray and blue. Her eyes switch between gray and blue as well.