Chapter 13 - "Gryffindor versus Ravenclaw" - In which Ron and Hermione's anger grows, Quidditch practice resumes, Gryffindor plays Ravenclaw and wins despite Slytherin's attempts to sabotage the match by dressing as dementors. Gryffindor celebrates into the night while Hermione studies. Black gets into the dorm and apparently slashes Ron's bed curtains.
Harry arrives for his first anti-[dementor] lesson with Lupin, and learns about the [Patronus Charm]. He attempts it on a [boggart], but hears his parents' last words with every attempt. As he leaves, he gives himself a pep talk - determined to succeed despite this meaning he wouldn't be able to hear his parents' voices again.
As time passes, [Oliver Wood] ups the number of weekly [Quidditch] practices to five, leaving Harry only one night a week for homework. However, Hermione is even more bogged down - and neither Harry nor Ron can figure out how she's getting to her classes.
At the end of Harry's fourth anti-[dementor] lesson, Lupin reminds him that he's doing very well for being thirteen. They then sit drinking [butterbeer] together, talking about Sirius Black and the [dementor's kiss].
In the Common Room
Outside Gryffindor Tower, Harry and Ron run into Neville, who despite having written down the week's passwords has lost them. Finally Sir Cadogan lets them through, and Harry is immediately surrounded by fellow students admiring his [Firebolt].
Harry sits down to chat with Hermione about her course load, but they're interrupted when Ron suddenly bursts from the [dormitory], having discovered Scabbers's blood amidst some cat hairs from Crookshanks.