Before the events of Undertale, W. D. Gaster and his two sons, Sans and Papyrus, live out their lives in the lab at Hotland. With their father consumed in his work, Sans has to juggle his responsibilities as his father's son and lab partner, as well as his responsibilities to his neglected little brother, all the while discovering the secret behind his father's true research.

A summary of angst and feels and happiness seen throughout The Property of hate, told in RGB's point of view.