The cold and damp Azkaban Prison stood atop a cliff on a lonely island in the North Sea. CRASHHH! Waves slammed against jagged rocks far below, sending salt-spray hissing into the wind. WHOOSH… A sharp gust of sea air howled through the narrow iron window. Dementors floated silently in the sky above, their robes fluttering like torn shadows. Inside a shadowy cell, Sagres Greengrass sat unmoved on a stone bed. A slender wand rested between his fingers, the tip glowing faintly silver. Flip-flip-flip.An old, tattered magical book hovered mid-air, its pages turning in a blur as invisible forces rearranged the runes etched across them. CLAAACK.The heavy cell door creaked open, metal grinding against stone. Sagres did not flinch. His wand continued to move. "What a 'great' surprise," he said calmly, eyes still lowered. "Since when did Azkaban start allowing visitors?" "For an old man like me, there are always some privileges." Dumbledore walked into the cell with a smile, his blue eyes observing Sagres through his half-moon spectacles. His robes shimmered softly in the dim light, starkly out of place amid the gloom. "Looks like they didn't assign you a roommate," Dumbledore said, placing a bag of lemon sherbets on the stone table. Sagres's fingers moved slightly, and the magical book in the air turned to ash and drifted down. He looked up at the old man, his gaze calm. "There are plenty of empty cells in Azkaban, Headmaster." "But they didn't even take your wand?" the old man said, blinking playfully. "I understand your confusion. After all, it was you who personally cast the Trace on my wand. But now…" He waved the wand in his hand, his calm tone revealing a trace of pride. "Even the Dementors can't detect the magical signature from it." Dumbledore didn't reply. Instead, he looked around the cell, eventually settling his gaze on the anti-magic stone bricks of the wall—covered in carved magical formulas. "It seems that even here, you haven't stopped researching," he said, leaning in to get a closer look and reading softly, "'Emotional Magic Energy Conversion and the Symbiotic Relationship with Dementors'—looks like your prison life hasn't been too bad. Maybe this place can't hold you at all?" The old man smiled and popped a fizzing sherbet into his mouth. "Just passing the time," Sagres replied, waving his wand to erase the markings on the wall. "Perhaps it's old age catching up with me, but lately I've been thinking… expelling you from Hogwarts five years ago might have been the greatest mistake of my life," Dumbledore said with a sigh. Sagres frowned at those words. "Professor Dumbledore, if you've come to mock my situation, you can leave. Studying those foolish Dementors is already enough to bore me—I don't need another self-righteous visitor." Dumbledore sighed, a trace of helplessness in his tone. "Sagres, I never intended to mock you. I expelled you back then because I believed your research had touched upon dangerous edges.. I had to think of the safety of the students at Hogwarts." "Dangerous, huh?" Sagres shook his head. "Magic itself is dangerous." He tapped his wand on the stone bed and conjured an oak chair. "Of course, I understand your actions at the time, and I've never held a grudge against you for them." Hearing that, the old man smiled again, pulled the chair over, and sat down. The oak seat let out a soft creak. "I'm quite glad to hear you say that. After all, in the five years since you left Hogwarts, you haven't contacted me even once by letter." Dumbledore's half-moon spectacles caught a faint glint of light. "I heard about your situation from Filius. I know you've never stopped seeking the true essence of magic all these years, and now you've achieved remarkable results. To be honest, I'm genuinely pleased." "If you're here for a purpose, I suggest you speak plainly," Sagres interrupted, raising a hand. "You've done enough preamble." "Ah, of course. What I mean is, based on your past achievements, you deserve a better research environment." As he spoke, the old man drew a wax-sealed letter from his robes. "At the same time, Hogwarts is in need of a Charms Consultant—someone to guide senior students in their theoretical research and practical work on spells, teaching all those who've passed their O.W.L.s." Sagres took the letter but didn't open it. His fingertips brushed over the Hogwarts crest on the seal as he murmured, "Return to Hogwarts?" His thoughts wandered, and memories of his time as a student at Hogwarts surfaced. Truthfully, that had been a "peaceful" and "wonderful" time. Dumbledore didn't press him. After a while, Sagres returned to the present. "I think I can accept. But Professor, this will require you to use your position as a Wizengamot adjudicator to allow me to leave here legitimately." "Of course. I'll handle all of that," Dumbledore said, rising to his feet. "The Ministry will deliver your pardon order first thing tomorrow morning. Besides that, Sagres…" "Afternoon tea every Thursday in the Headmaster's office, and…" He paused briefly. "When the castle needs it—protect it in your own way." The cell fell briefly silent, the only sound the crashing of the North Sea filtering in through the iron window. Sagres walked to the stone table and tapped the bag of lemon sherbets with his wand. The sweets arranged themselves into a miniature model of Hogwarts Castle. "I can agree to that, Professor Dumbledore." The sugar-crafted towers gleamed translucent under the moonlight. "But I have two conditions." "Go on." "First, my research is not to be interfered with by any so-called Ethics Review Committee." With a flick of his wand, the candy model of the castle collapsed with a crash and reassembled into a complex three-dimensional rune structure. "Second, when I deem certain 'traditional wisdoms' to be obstructing the truth, I reserve the right to initiate educational reform." Dumbledore gazed at the floating sugar rune structure—it was a form of ancient Norse rune magic. He remained silent for a long moment, then calmly extended his hand. "Then welcome to Hogwarts, Professor Greengrass." Sagres smiled and extended his right hand as well. "This time, wandering into the Restricted Section of the library won't be a violation of school rules." "Indeed, but please don't replace the index page of Moste Potente Potions again," Dumbledore said, blinking. "Madam Pince still believes it was a misfile on her part..." As he watched Dumbledore disappear via Phoenix Apparition, flashes of memories that didn't belong to this world occasionally surfaced in Sagres's mind: glass beakers in a laboratory from another universe, chalkboards covered in formulas, endless experiments. But those scenes were always swiftly pushed aside by reality—the look of disgust from his family in childhood, his mother's screams... the Cruciatus Curse... and the cold silhouette of his father walking away... As a transmigrator, Sagres had once felt pleased with his setup at the start. After all, most people who received a transmigration script ended up as orphans with dead parents, while he had both parents alive and came from one of the Sacred Twenty-Eight—the Greengrass family. In his initial vision, as a noble of the wizarding world, he imagined he would at least live a life free from want, enjoying the wonders of magic in a leisurely, carefree manner—perhaps even setting up a hedge fund to short Gringotts or something similar. Let these old fossils of the magical world experience what was called "Muggle ingenuity," and properly fulfill a sense of personal value. But reality had quickly dealt him a heavy blow. From the moment he transmigrated to this world up until before he entered Hogwarts, the British wizarding world had been shrouded in Voldemort's rule. That's right—he knew Voldemort would eventually be defeated, but at that time, the Dark Lord was still very much in power, and the Boy Who Lived was still in his mother's womb. Most importantly, all he knew was that Harry Potter would be the savior, Voldemort the great villain, and that Harry would ultimately defeat him. But as for when or how that would happen, he had no idea. And the Greengrass family, as die-hard supporters of Voldemort, was made up almost entirely of Death Eaters. His father was a silent and taciturn Unspeakable in the Ministry of Magic, and his mother was a Muggle-born witch. Yes—Sagres was a half-blood. Though his mother was a beautiful Muggle-born witch, she deeply despised Sagres's half-blood lineage. She made no effort to conceal her hostility toward him, as if by doing so, others would forget that she herself wasn't pure-blood. If it had only been the hatred and abuse from his family, that might have been tolerable. But later, the Greengrass Death Eaters, in order to demonstrate their loyalty to Voldemort's pure-blood ideology, actually used Sagres's mother as a sacrificial offering. That pitiful woman, once devoted to and supportive of the Death Eaters, was tortured into madness with the Cruciatus Curse by the very people she revered—and then finished off with a Killing Curse. Just like that, her life came to a hasty, meaningless end. When Sagres learned of this, he didn't even know whether he should feel happy or sad. Because aside from giving him life, that so-called mother had given him nothing but endless curses and torment. At the time, five-year-old Sagres had just experienced the first magical outburst of his life. He didn't even own a wand yet, but he was already forced to confront his reality. The thing he muttered most often back then was: "This is worse than being an orphan!" He had no choice. The threat of death left him with only one path—to seek help from magic. And so, at the mere age of five, Sagres, backed into a corner, ended up creating the first spell of his life. Yes, after that initial outburst of magic, he discovered his own golden finger—when the magic within his body accumulated to a certain threshold, he could forcibly improve or even create spells from nothing. Enhanced Confundus Charm—this modified version had no offensive power, but it could make people subconsciously ignore his presence. For someone who was already invisible in his own family, it was the perfect fit. Using this charm, he hid himself and lived on edge in that household for six years. In all honesty, it was nothing short of a miracle. Later, he received his Hogwarts letter. On the eve of his departure, he personally sent two Death Eater relatives—who had once cast the Cruciatus Curse on him—to Azkaban. As for his father, he had already been sentenced to prison when Voldemort fell—most likely already dead by now, kissed by a Dementor... Flap, flap—a raven landing at the window broke his train of thought. Sagres took the scrap of Dementor cloak from the bird's beak. With a tap of his wand, the fragment turned to ash, and a wisp of ghostly blue energy flowed into his body. The flame-shaped rune scar on his wrist glimmered faintly under the moonlight—a souvenir from a dark magic experiment, and the very reason he could walk through Azkaban unafraid. "It's time to leave."