The second half of this drama, according to the Weasley Brothers' plan, was supposed to take place in the second-floor corridor. Su Er did not go to watch the fun, because the outcome was already settled.
He took another route toward the top floor of the Castle.
This was another unusual feature of Hogwarts Castle: animals had passages of their own, something Su Er had only recently discovered.
If Hermione was not in the common room, she had to be in the Room of Requirement. Apart from the Library, nowhere else offered her such peace and quiet for studying.
Moreover, the all-capable Room of Requirement could provide Hermione with books while she studied, except for those in the Restricted Section. Although its selection was not as comprehensive as the Library's, it could solve her problems most of the time.
More importantly, as the days grew colder, between a quiet place with a fireplace and an equally quiet but icy Library without one, surely the choice needed no further explanation? Provided you had a reasonably normal brain.
"How many hats have you made?" Su Er reverted from his Animagus form as soon as he entered the Room of Requirement, and immediately saw Hermione directing several long needles and some yarn with her wand to knit hats.
With her previous experience knitting Su Er a scarf, she managed it with reasonable ease.
"Oh, you're here." Hermione looked up with a radiant smile, then proudly tipped her chin toward the side. "Look, I added a few little decorations, so I can give them to female and male house-elves separately."
"Not bad..." Su Er walked over, picked up a hat, examined it from both sides, and offered a word of praise.
"Heehee." Hermione giggled happily, keeping her wand moving in a steady rhythm.
"Are