I've been meaning to do this for a while -- I'm going to try and cobble together a guide to canon Slytherins. Today's topic is Pansy Parkinson. Below you'll find direct references to Pansy in canon, then a summary of canon facts/trivia, then some of my own extrapolation of what Pansy could be like outside of Harry's field of view based strictly on canon.
If you have thoughts on canon!Pansy or information from non-book sources (JKR's interviews and the like), I'd love it if you shared. I'll update this post with any other insights/trivia. If you have thoughts on Pansy as she is written in fan fiction, check out this discussion started by starrysummer.