The Normal People are a group of people shown in a lineup in S1EP6. They consist of a Middle Aged Man in a Red Shirt, a Sassy Young Hispanic Girl, and a Short Pale Business Woman.
Despite apparently being normal people, they are all incredibly short. The Man is 5'3, the Sassy Girl is 5'0 and the business woman 4'8. This seems to back up the fan theory people in the Dan Vs Universe are shorter on average.
The Middle Aged Man appears in the background in several episodes.