There are hundreds of thousands of Harry Potter stories written by fans. I wanted to know how they compared to the original series, so I took a look at story data from one of the internet's biggest fandom sites.
To set the scene, here's a picture of all relationships from the seven original Harry Potter books by J. K. Rowling. Each circle is a character, colored male or female, with lines indicating romantic pairings.
Lines are colored by whether the relationship is straight, male-male, or female-female.
In the original series there's only one same-sex relationship (between Albus Dumbledore and Gellert Grindelwald) and even that one was only obliquely alluded to in the original books.
In fanfic, things look very different.
Here's the same chart, now with lines connecting characters who are romantically linked in fanfiction, and with the popularity of the relationship represented by the thickness of the line.
Click a character to see only their relationships.
Well, that look different! A lot more diversity across the board, but in particular there's a huge increase same-sex pairings.
Some characters, like Hermione, are still mostly straight in fanfic romance stories. Others, like Sirius Black, have a much higher proportion of same-sex relationships.
We can make a chart that plots this data to find the “gayest” and “straightest” characters in fanfic — those with the highest or lowest fraction of same-sex relationships. This time we'll include all characters who went to Hogwarts and sort them by house.
In the picture below, each circle is a character, sized by popularity and positioned on a scale from 0% to 100% based on the percentage of their relationships that are with characters of the same sex.
Female characters are less likely to feature in same-sex relationships than male characters, and while some of the popular Gryffindors are up there, the cluster of Hermione, Ginny, and James & Lily Potter near zero balance out the score for Gryffindors.
Slytherin on the other hand has very few characters at the low end of the scale. At the same time, the most popular Slytherins, particularly Draco, Snape, and Voldemort, score highly.
So, what's the gayest house?
Looking at the percentage of same-sex relationships by house, the conclusion is clear: the gayest Hogwarts house is Slytherin. 🐍 🏠 🌈
This stays the case if we look at character-level means or medians by house or even remove a popular character or two, since characters have relationships across houses.
If we limit our analysis to male characters only, things look different: Gryffindor places first, followed in order by Ravenclaw, Slytherin, and Hufflepuff. You can see for yourself by clicking these links to transfigure the chart above: male only, female only, or both.
To round this out here's the chart for everyone else who didn't go to Hogwarts:
Tune in next time when we explore the giant squid. 🦑
You can return home or see the code.
Thanks to Yuriy Rusko, Zora Killpack, Mitha Nandagopalan, Ben Kuhn, Ben Cartwright-Cox, Julie Cris, Anthony Vastano, Moritz Stefaner, and Dan Luu for comments on drafts of this post and help with research.