Sectumsempra

Clara hugged the book to her chest as though it were a treasure and walked out of the Headmaster's Office with a light step.

She looked down at the ring on her little finger. Its silver pattern glinted in the candlelight, and Gabriel's petals opened slightly, as if waiting for something.

She found Cedric in the corridor outside the library. He had just come out, carrying two hefty spell reference books, and a tuft of his hair had been lifted by the draught. When he saw her, he looked startled for a moment, then broke into a grin.

"Hi, Clara. Looking for someone?"

"I was looking for you, Cedric." She pulled the book from under her arm and held it out to him with both hands. "This is for you. As a thank-you for helping me sort out that business in the common room last time."

Cedric blinked and took the book, apparently not expecting there to be any follow-up to that incident.

Clara went on, "It's called Defence Against the Dark Arts: Principles and Counter-Curses. I happened to find it in Knockturn Alley. It's a manuscript by a fifteenth-century Welsh witch. I thought you might find something useful in it while you're preparing for the Third Task. I passed the Forbidden Forest a couple of days ago and happened to see Ministry of Magic officials asking Hagrid for Blast-Ended Skrewts. If even Blast-Ended Skrewts are going to be in the Third Task, there might be other things too. It never hurts to learn a few more obscure counter-curses."

"You found it in Knockturn Alley?" Cedric looked down at the book in his hands, sounding a little surprised. Knockturn Alley was hardly a safe place, with Dark wizards gathering there. He had been once with his father and had always found it sinister. Yet this younger schoolmate of his had actually gone there to buy an antique book, which didn't seem to fit his impression of her. "I never would have guessed."

Cedric smiled and opened the silver chain, but when he turned to the first page, the book snapped shut.

"Oh!"

Cedric drew a sharp breath and looked down at the tiny wound that had suddenly appeared on his right index finger. A bead of blood welled up on his fingertip, gleaming dark red in the corridor's candlelight. It was the first time Clara had seen him look so surprised.

Clara silently thanked Merlin. Merlin be praised, nothing went wrong.

"I'm sorry, I was just about to tell you," Clara said, stepping forward with just the right amount of apology on her face. "This book has a bit of a temper. It bites the first time it's opened. Wait a moment, I still have some gauze and ointment left in my pocket from last time."

She took the wound ointment from her pocket and pulled Cedric's right hand toward her through her sleeve. She applied the ointment quickly and gently. The instant Gabriel on her ring touched the bead of blood, its petals closed softly, sealing the blood sample inside its silver centre. The whole process took less than two seconds.

"There, now to wrap it in gauze." She looked down and searched her pocket for the roll of gauze. Her fingers had just touched the coarse cotton when she heard Cedric draw a quiet breath.

Clara looked up and followed his gaze. Cho Chang was coming around the corner of the corridor, carrying two books, her long black hair swaying gently against her shoulders as she walked. She hadn't noticed them yet and was looking down at the title page of the book in her hands.

The tips of Cedric's ears turned a shade redder before Clara's eyes. He quickly pulled his finger out of her hand, the movement gentle but hurried, as if a spell had burned him.

"Thank you, Clara. I can manage on my own."

Clara looked down at the gauze she hadn't yet had time to unroll, then at his face, which plainly said, "Please don't put gauze on me right now," and understood at once. She stuffed the gauze into Cedric's hand and promptly took a step back.

Cho Chang spotted Cedric and walked over to them. She raised her head, her gaze falling first on the ointment-covered finger Cedric was holding up, then on the thick book with the dark green cover in his arms. A hint of curiosity crossed her face.

"Ced, what happened? Didn't you say you were going back to the common room first?" she asked softly.

"The book bit me," Cedric said, holding up the finger, his tone somewhere between resignation and self-mockery. Then he tilted his head toward Clara. "This is Clara Albert. You should have met her before; she's in my house. She gave me a Defense Against Dark Magic book from Knockturn Alley as a thank-you, but it has a bit of a temper and bit me before I'd even opened the first page. She helped me treat the wound."

He turned to Clara, his voice returning to its usual warmth. "Clara, this is Cho Chang. She's a fifth-year in Ravenclaw."

Cho Chang smiled at Clara and held out her hand.

"Hello, Albert. I saw you at the Yule Ball. You danced the opening dance with Potter. I remember you wore a silver-white dress; it was lovely." She glanced down at the book in Cedric's arms. "Did you give him that? Things from Knockturn Alley really do tend to have little tempers. Last time I bought an old ink bottle there, it sneezed at me whenever I opened it and sprayed ink all over my face."

Clara smiled and shook her hand, then put the jar of ointment back in her pocket.

"Perhaps the book felt it had been neglected for too long and needed to show its new owner who's boss first. But it won't bite again after this, at least according to the bookshop owner."

"I hope you're right." Cho Chang smiled, released her hand and turned to Cedric, her gaze settling on the ointment-covered finger. "Do you still need help? With the bandage?"

"Probably. It's not very convenient, having hurt my right hand."

Cedric handed her the gauze. His uninjured hand paused in midair, and his fingertips accidentally brushed the back of Cho Chang's hand. The tips of his ears immediately went from pale red to deep crimson before their eyes, as if someone had cast a Colour Change Charm on them.

"Clara, thank you for your gift. The book and the gauze are both important."

He was probably also thanking her for creating an opportunity for him to get close to Cho.

"I gave you the book, so I had to take some responsibility when it bit you. Professor Snape needs to see me, so I'll go first." Clara smiled and spread her hands at them, then looked at Cedric. "Good luck with the Third Task."

She turned and headed back down the corridor without hesitation. Behind her came Cedric's explanation in a lowered voice and Cho Chang's soft laughter.

A touch of bitterness passed through her heart, but it quickly faded. Taking the blood had gone even more smoothly than she had imagined, and the last problem in making the protective charm had been solved. What she had to do next was save him to the best of her ability, or learn the whole truth about that night.

But she had another problem to deal with now.

Snape's Defence Against Dark Magic Class.

Perhaps because there was no Potions Class today, the candles in the dungeon were dimmer than usual. Only the two beside the desk were lit, their flames casting wavering shadows on the damp stone walls. Snape stood in the middle of the classroom, his black robes almost blending into the shadows in the dim light.

"Oh, Miss Albert, I thought you would take longer with Mr. Diggory. But it seems your efficiency is adequate."

Clara automatically took Snape's sarcasm as praise. While he was speaking, she tied up her hair and picked up her wand, preparing to cast the Shield Charm as she had countless times before.

"Put the Shield Charm away," he said.

Clara paused. Over the past few months of training, the Shield Charm had been her most frequently used means of protection.

"Today's training is no longer about defence," Snape's voice echoed between the dungeon's stone walls. "You have learned how to protect yourself against harmful spells. These things can keep you alive, but merely staying alive is far from enough when facing a real Dark wizard. Death Eaters will not stop and applaud you because you blocked their first spell. They will keep attacking until you leave an opening. In that situation, you have only one choice: take them down before they take you down."

As his words ended, three moving training dummies appeared in the room.

He raised his wand and pointed it at a training dummy.

"Stupefy." The red light struck the dummy squarely in the chest, sending it flying backward to crash heavily into the stone wall.

Clara had learned this spell before, but it had never been so destructive. Before she could recover from her shock, he flicked his wand again. The dummy exploded into pieces, scattering splinters everywhere.

"Reducto."

Then he turned to face the last dummy, his wand tracing an extremely fine arc. A deep cut suddenly opened across the dummy's body, as if an invisible blade had slashed it from shoulder to waist.

"Sectumsempra."

Clara instinctively drew a sharp breath.

"This is not Dark Magic. I would not risk sending you to Azkaban," Snape said. "The wounds caused by Sectumsempra cannot be healed with ordinary healing spells. On a battlefield, the person struck will continue to bleed until someone uses the specialised counter-curse on him. It will not be fatal, but it can buy you some time. Now, pick up your wand."

Snape waved his hand, and the three dummies stood up again, restored to their original condition.

Clara took a deep breath, stepped into the place he had vacated and raised her wand at the first dummy.

"Stupefy." The dummy swayed and staggered half a step backward.

"Miss Albert, do not hesitate, and do not hold back. Imagine they are Death Eaters who want to kill you, not classmates who pose no threat to you in a lesson."

Clara steadied her breathing.

"Stupefy."

The red light struck the dummy in the chest with such force that it flew backward and slammed into the stone wall, splinters pattering down from the point of impact. Snape made no comment, merely lifting his chin to signal her to continue.

"Reducto."

The second dummy exploded over a wider area than Clara had expected. Fragments landed on the workbench, and a severed wooden hand rolled to Snape's feet.

"Sectumsempra."

Clara swung her wand along the arc she had memorised earlier. She had never seen this spell in any book, but its destructive power was truly astonishing.

A faint scratch appeared on the dummy's surface. She frowned and adjusted the angle herself without waiting for Snape to speak. A second spell followed close behind, making the cut twice as deep and driving it into the dummy's torso. She didn't stop. She cast a third spell in succession, the blade-like cut deepening precisely along the path of the first. The dummy's entire left arm came off and struck the floor, raising a small cloud of dust.