You're the Heir of Slytherin!

Sunday afternoon, Hufflepuff Common Room.

Justin was engrossed in Lockhart's A Stroll with a Banshee.

"Why are you reading a textbook on a Sunday?" Gavin had just returned from the Room of Requirement, and the sight surprised him.

Ernie, however, was used to it. "He's fallen in love with Lockhart. I suspect Lockhart slipped him a Love Potion."

"Slander! I still like girls, even in the United Kingdom!" Justin protested, his face bright red. "I just think Lockhart's handsome."

"Ever since he walked you through that Freezing Charm?" Ernie's memory was precise.

Justin fell silent. Ernie's memory really was good. After that lesson, Justin's confidence had soared. He'd started believing in his Defense skills—and admiring Lockhart along the way.

Gavin raised an eyebrow and was about to speak when he felt a flick against the back of his head.

Someone had triggered the Transfiguration Spell sensor he'd placed in the Girls' Bathroom.

He stood at once, startling both his roommates.

"What's wrong?" Ernie asked, staring at Gavin.

"Going to the girls' bathroom." Gavin left as calmly as he'd stood up.

"Huh?" Justin looked at Ernie as if he'd seen a ghost. "That's how he brushes us off now?"

Ernie nodded. "My mum says love makes people lose their minds."

Justin thought of Cordelia and found the explanation convincing. "It certainly does."

Gavin didn't go straight to the Second Floor Girls' Bathroom. First, he ducked into the first Empty Classroom along the corridor and spread the Marauder's Map on the windowsill.

"I solemnly swear that I am up to no good."

Ink spread across the parchment. In the deepest stall of the Second Floor Girls' Bathroom were four names: Hermione Granger, Harry Potter, Ron Weasley, and—Cordelia Rowle.

Gavin stared at Cordelia's name for a moment, unable to understand why she was