1. (noun) One who has never read/objects to/is not completely obesessed with Harry Potter or anything associated with the series
2. (adj) describes a person/idea that is against Harry Potter or the series.
Person 1: Hey do you wanna go to see the new Harry Potter movie with me?
Person 2: No thanks, I'm a faithful Potterstant.
The idea that Hogwarts is satanic is completely potterstant!