By the Black Lake, teacher and student got along in perfect harmony.
They talked about all sorts of things: Professor Flitwick's first meeting with Will, his disappointment when Will wasn't sorted into Ravenclaw, how Will's outstanding performance had only made him fonder of the boy, and how Will's research had been questioned in his third year... Four or five years had passed in the blink of an eye.
They chatted and laughed, utterly at ease. Only when the last of the sun hung low and shadows covered most of Hogwarts did they head back to the Castle through the evening glow.
"Oh, and Will," Professor Flitwick said before they parted, "make sure you get some rest."
"I will, Professor Flitwick. Good night."
"Good night. Get to bed early."
[You gained new knowledge of charms. Charms experience +1] [You gained new knowledge of charms. Charms experience +1]
That night, after spending half the evening poring over Professor Flitwick's notes, Will took a swig of Grape Juice, cast a Clear-Headed Charm on himself, closed the notes, and headed out.
A few dozen seconds later, Will appeared in the Laboratory in Phoenix Form.
It was called a laboratory, but it looked more like an evil wizard's lair. It had two levels: Will conducted his research upstairs, while the lower level held the test subjects' cells.
Every test subject wore shackles on their wrists and ankles. Will had also cast Sleep Charms on the werewolves, who spent most of their time asleep.
It was late at night, and everyone was sleeping. Will brought a werewolf he had used for Memory Charm experiments up to the second floor. Of course, with the full moon still days away, the werewolf was in human form.
He had used this werewolf in earlier memory experiments.