Potions was her favourite subject, for Professor Snape made a particular pet of her after she showed up Harry Potter so decidedly in their first class by answering all the questions Potter couldn’t, earning fifteen points for Slytherin in the process. It also earnt her the respect of her Slytherin peers, and jealous glares from Potter and Weasley. It wasn’t her fault if they hadn’t studied! They didn’t seem to learn their lesson quickly either – they seemed woefully underprepared for every subsequent class. Why wouldn’t you study the potions in advance? It made brewing, and answering questions, so much easier.