Arya finds some good aspects to servitude at Harrenhal, namely a straw bed and regular meals. Hot Pie eats even better in the kitchen, and Gendry was sent to work as a blacksmith at the forge.
Her taskmaster, Weese, is a bit of jerk, though, as he hits at the slightest provocation, and his dog is even meaner.
One day, a group of sellswords called the Bloody Mummers arrive at Harenhal led by Vargo Hoat.
During their stay, she learns her brother's army, the part led by Roose Bolton, is nearby at the ruby ford of the Trident. The Bloody Mummers leave soon after.
Another party arrives days later, this time led by Ser Amory Lorch, and Arya is surprised to see Biter, Rorge, and Jaqen H'ghar with them.
That night in bed, Arya is awoken by Jaqen. He says that a man pays his debts, and since Arya stole three lives from the Red God by saving them, Jaqen owes her three deaths. Sweet, free deaths.
Later, the Mountain also swings by Harrenhal with his men. While Arya is serving the Mountain's men, she overhears Chiswyck telling a story about the Mountain raping a poor girl as though it were an uproarious joke.
She finds Jaqen and whispers Chiswyck's name in his ear.
Three days later, Chiswyck is found dead, having supposedly fallen from the wallwalk drunk off his butt.