Hagrid swiftly integrated himself into the party. Draco could hear him on the Extendable Ear, bellowing some song about a red-nosed reindeer, an intriguing beast he never had introduced in Care of Magical Creatures. Draco thought he could use a reindeer-powered sleigh right about now, since his dreaming self lacked a wand. Without it, he could not Apparate or even call the Knight Bus to get home to his own bed.
Left shivering on the park bench, Draco continued to watch the holiday merriment inside the Potters' home. He observed Goldstein flirt with Granger in an awkward manner that she seemed to find endearing. Draco found it appalling, but he could not bring himself to leave the park bench and go inside to the party.
It would be pointless, he knew. He had lost her, through his arrogance and unwillingness to own up to his shortcomings as a father. He had lost Scorpius, too. As Hagrid and Flitwick both had said, he was too late. While Astoria's funeral had been packed with sincere mourners, Draco knew he was going to die alone and unmourned, consigned to the family crypt by Scorpius with dull relief rather than grief. That was how Draco had felt when his own father died.
The third creature Lucius had warned him about glided towards him. The Dementor drew in a deep, rattling breath, relishing in Draco's despair.
It's just a nightmare, he told himself. I'll wake up soon. But as he sat on the bench, defenseless and frozen in terror as the Dementor approached, Draco was increasingly convinced he would never wake up. He would be found dead - or worse, Kissed - in his bed on Christmas morning.
The creature loomed over him, its hooded robe billowing with a gust of wintry wind. Draco's teeth chattered with cold and fear as the Dementor reached out with a skeletal hand and tilted his chin upwards. His worst memories - those Flitwick had shown him, plus the atrocities he had stood witness to as a reluctant Death Eater - played through his mind in a rapid, incessant loop. In futile desperation, he jerked his head away as the Dementor leaned in. "No, please! I'll do anything! Please, give me one more chance!"
"You deserve to be happy, Draco!" It was a woman's voice, a melding of Granger's bossy alto and Astoria's breathy soprano. "Expecto Patronum!"
A brilliant light shot from the front step of the Potters' home. The Dementor shrieked and released Draco, knocking his head back against the park bench before fleeing.
"Ow!" Draco's eyes shot open. He was in his own bed, morning sunlight streaming through the open curtains, the covers tangled at his feet. "Thank Merlin. It was only a dream," he muttered, rubbing the knot on his scalp that he must have acquired by knocking against the headboard during his vivid nightmare.
He sprang from the bed and grabbed his discarded work robes from the day before, hastily donning them as the last words from his dream echoed in his mind. Draco had been given one last chance at happiness, and he intended to make the most of it.