Spengler's Assistant aided Egon in his studies of human emotions. She would often brief Egon when a test was ready to begin. When Dana Barrett consulted Egon with the incident on First Avenue, Egon informed the Assistant they would be moving on to the happiness index next. She left and returned when the affection test was ready to begin. After Dana left, Egon told the Assistant they would next test what happens when they took away the puppy from the test subject.