Buffy Summers - Gryffindor
Alexander "Xander" Harris - Gryffindor
Willow Rosenberg - Ravenclaw
Rupert Giles - Ravenclaw
Angel, FKA as Angelus, FKA Liam - Gryffindor
Cordelia Chase - Slytherin
Daniel "Oz" Osbourne - Hufflepuff
Spike, FKA William the Bloody - Slytherin
Faith Lehane - Slytherin
Riley Finn - Hufflepuff
Tara Maclay - Hufflepuff
Anya Jenkins - Slytherin
Dawn Summers - Gryffindor
I sincerely apologize for not having sources for my .gifs. They're all from a folder of reaction gifs on my computer that I've saved from Tumblr. If you know who created them, feel free to comment and I'll add a source.
Also, I know that I'm not the first person to do this. Also ALSO, I used this site as a reference, in case you're wondering where some of my explanations came from.