This is a cooccurrence matrix based off of Les Miserables Co-occurrence only with Harry Potter characters, where cooccurrence is defined as if two characters are tagged as characters featured in a given fan fiction. Therefore the diagonal values are all the same, since every fan fiction that has Albus Dumbledore also has Albus Dumbledore.
Instead of the intersecting values being the number of fan fictions between two characters, the number is normalized by dividing by the number of total fan fictions about that character. Therefore, the value in [Draco Malfoy][Harry Potter] is most likely not the same as [Harry Potter][Draco Malfoy]. This allows us to see some interesting properties- for example, of all Lupin fan fictions, 16.23% also feature Tonks. However, of Tonks fan fictions, 70.57% also feature Lupin. This shows perhaps a conflict in the fandom of who else Lupin is spending a lot of time with in fan fiction... WolfStar, anyone?