"- takes the form of whatever we fear most. As such no one has ever seen the true shape of a boggart," She finished breathlessly.
"Excellent! Ten points to Ravenclaw for a perfect answer!" beamed the professor. Her face flushed with pride at this praise, oblivious of her partners' sudden change in composure. Harrys' face remained impassive, but this news roused him from his current internal struggle, realising that it was about to answered for him, in front of the one person he wished to keep his fears secret from.
Surveying the worry on the faces of his class, Professor Lupin chuckled heartily, causing the two cabinets behind him to shudder violently, "Fear not younglings, this is a defense class and so defense we shall learn, against even our worst fears!"
Harry barked out an em-bitter "Ha!" causing both his partner and professor to cast worried glances in his direction. Cursing himself silently, he attempted a wan smile, passing his outburst of as amusement. Neither looked convinced.
The shrieks and screams of the other 3rd years meant little to Harry as his unfocused eyes, glazed by concentration took little in. The sounds in his ears made little sense too, as he galvanized himself to forget his fears.
Suddenly, there was a bang and in front of him stood the figure of a girl. As the smoke cleared, Harry could make out strawberry-blond, mid-back-length hair, icy blue, dispassionate eyes and a quirked mouth, almost as if permanently set to laugh at the world. She stared at Harry in disbelief, unable to comprehend how she could be part his greatest fear. Harry stood stock still, open mouthed, caught completely off guard by this unholy doppelganger.
A tremor quivered down his frame, his shoulders shook and she moved to comfort him, but then caught what Harrys' wide eyes were fixated upon. In the doubles' hand, was a bloody, beating human heart. The double smiled at Harry, cradling the heart as if it were a small child. She saw Harry relax, his relief palpable, but the clone wasn't finished.
With its thumb and index finger tips only, the boggart gingerly lifted away the heart, and held it at arms distance. Her heart wrenched at the tortured expression Harrys' face took on, she could see his knees trembling, about to give way. Then, seemingly without a second thought, the double looked the other way and dropped the heart to the floor and walked back off to the cupboard, where it was met by an older boy of blonde hair and pale skin, who held the doppelganger lovingly, as if to protect it from the trauma it caused.
Both quickly backed into the cupboard waving cheerfully to Harry who was by now on his knees, his eyes swimming with what appears to her for all the world to be liquid sadness. They shut the door and Harry collapsed forward onto his arms, the tears now falling freely to the floor. "no...please..." he choked out hoarsely.
She fell to her knees beside him, knowing somehow that she was the one he begged for. Harry jerked back, "I'm so sorry..." he whispered, his tearful, upturned face looking up at her. When he ran for the door, she had heard such vulnerability in his voice she hadn't the heart to chase him down and have him explain.