Sunday, the 1st of September 1996

Severus emerged from the fireplace without ceremony. Lord Greengrass stood before him and regarded his guest. The drawing room's dais, upon which the traditional offerings of bread and salt would ordinarily be laid, hovered empty. Severus took note of this but made no sign that it bothered him.

"Lord Greengrass."

"Professor Snape."

"Lord Slytherin has many virtues, but it is regrettable that patience is not among them."

Lord Greengrass furrowed his brows. Only Severus, he mused, could deliver a death threat with the air of someone complimenting the wallpaper.

"My daughter will arrive presently, as per our arrangement."

"Let us hope so."

On cue, the door swung open to admit a girl on the cusp of womanhood. Her blonde hair was undone and flowing, and she was dressed in deep viridian robes that emphasised her svelte figure without immodesty. Above her breast she wore her sigil: the fir branch of her House, lush and ancient. Lord Greengrass felt a flicker of pride, which was promptly snuffed out when he remembered the reason for her formal vestments.

"Father," she said, "Professor."

"Daphne, I trust that you are ready?"

"Yes, Father." She gave him a reassuring look, which he did his best to return.

"Professor Snape will escort you."

Severus looked questioningly at Lord Greengrass, and upon seeing a small nod, reached for the bowl of floo powder. "The Serpent's Eyrie," he called, and the fireplace roared to life.

"After you, Miss Greengrass." She obliged, and stepped through the flames.

Daphne Greengrass fought to rein in her awe. She had accompanied her father on social calls to the Malfoys as a child, and recalled the drawing room to be capacious, but not grandiose. The room she now found herself in, however, was little short of palatial: obsidian serpents with emerald eyes embossed the hearth whence she emerged, and the walls were draped in radiant livery. The ceiling seemed much farther away than any sensible architect would allow, and supported a massive chandelier with countless emeralds. Everything was bathed in its viridescent light – not her House's verdant green of wood and stream, but an ominous, entrancing green: deep of shade and deep in magic.

"May I announce Miss Daphne Greengrass," said Severus, who had just emerged behind her. At the sound of her name, Daphne snapped to her senses.

"You are most welcome to my home, Miss Greengrass," came a soft voice from somewhere beyond. A silver platter materialised before her. At Severus' urging, Daphne broke off a bite-sized gobbet of bread and dipped it in salt, gingerly putting it into her mouth. She was somewhat surprised that it tasted ordinary.

"I now declare you under my aegis." At these words, the magic in the air seemed to twist, and the room's green pallor lifted. Daphne was now aware that she was in company: Lord Slytherin sat upon a regal chair, leaning slightly as though he was minded to take an afternoon nap. He looked to be little older than forty, and wore robes that were plain but impeccable. His hair bore the first strands of white, but age had kindly wizened, rather than diminished, his visage. On the whole he must be considered handsome – if not for his blood-red eyes that alluded to something inhuman.

He was flanked by almost a dozen wizards and witches who stood by placidly. Daphne recognised only the Lestranges, who looked haggard, and the Malfoys. Lady Malfoy had a dazed and milky look in her eyes, while Lord Malfoy's expression was inscrutable; he seemed altogether indifferent at his ancestral seat's annexation. Or expropriation, more like.

Daphne swallowed and stepped forward to present herself.

"Lord Slytherin. My father, the Lord Greengrass, sends his regards."

"Does he? I must say that I am glad to receive them." Lord Slytherin did not speak unkindly, but out of the corner of her eye Daphne saw some of his retinue smirk. "Miss Greengrass. I am told you are an able witch, and you must have felt the enchantments in this room. Can you describe them?"

Daphne paused. She was taken aback by the lack of pleasantries, and even more so by the question. It had been less than two months since her OWLs, and the last thing she expected from Lord Slytherin was yet another viva. Fortunately she had been considering the question for the past minute or so, and had reached at least a conjecture, if not an answer.

"My mind was hazy when I entered, which probably means there is a powerful confundus or trance charm – I think it's localised, maybe powered by the crystals in the chandelier. And the ambient magic is very dense, which is strange. The house is old but that's not enough to explain it. And everything cleared when I accepted the guest rite, so the protections must be tied to blood magic, to the master of this house…. that being Your Lordship, of course." Daphne made sure to mention her House's acceptance of his ancestry, as her father instructed.

Lord Slytherin acknowledged this with a thin smile. "There are a number of other… protections, far beyond a witch of your age. However, the locus of their power is as you say." Daphne let out the breath she did not realise she was holding. Lord Slytherin took no notice and continued, "Wormtail, it seems that for once you have not disappointed me. Young Miss Greengrass shows promise."

"Thank you, my Lord…" Daphne turned to look at the podgy man who had briefly emerged from the shadows, and slunk away again when Lord Slytherin waved his hand. She wondered briefly if "Wormtail" was an impressively prescient name or a mere sobriquet, until Lord Slytherin spoke again.

"Miss Greengrass, I will be forthright. I have a particular task that I need your assistance with, which your lord father assures me that you are eager to accept."

Lord Slytherin still spoke with the tone of a kindly and unassuming examiner, but the façade had abruptly fallen away. His piercing red eyes drilled into hers, and Daphne suddenly felt cold and very alone. She had not the foolhardy Gryffindor courage. But I am the heiress of the House of Greengrass, and our deep roots have weathered many storms. So she steeled herself.

"Yes, my lord, it would be a great honour."

"Tell me, Miss Greengrass: do you know of Harry Potter, the so-called Boy-who-Lived?"

"Yes, my lord, he is in my year at Hogwarts, but in a different house. Gryffindor." Though the thousand-year rivalry had never deeply concerned her, she made an effort to say the word with some measure of disdain – it being an obvious way to ingratiate herself with the purported Lord Slytherin, who seemed to approve.

"I have… met him, and found him to be entirely unexceptional. Yet Dumbledore has taken him under his wing, and many among the foolish believe he has the power to oppose me. Dealing with him will surely bring many to our cause. Unfortunately, Hogwarts' defences have proven to be robust. It remains difficult to take him by force, so I have resolved to take him by guile."

Lord Slytherin paused, the way Flitwick would when he invited questions after giving an explanation. Daphne had no idea what he was suggesting and kept silent.

"Unknown to many, Harry Potter is under the protection of an arcane ritual. Dumbledore believes it to have been woven by… love." Lord Slytherin spat the word out as though it was bile, and he paused again before continuing. "That being the case, the ritual can only be unwoven by that same power. It appears that you are uniquely positioned to assist, Miss Greengrass." He smiled without mirth.

Daphne felt like she was going to faint.

Lord Greengrass was nowhere to be found and Daphne did not seek him out. She was exhausted and retiring to her room suited her fine. Professor Snape had escorted her home, and assured her that yes, Lord Slytherin had indeed asked her to win Potter's love, and to persuade him to subject himself to a ritual that would rebind his protections to her, on pain of incurring great disfavour. And no, he did not expect her to succeed, but Lord Slytherin was a thorough man who was known to pursue many parallel paths to achieve the same ends. Of course he would not entrust the fate of his cause to a sixteen-year-old, but so much the better if she did somehow succeed.

Daphne Greengrass was not a girl to shy away from challenges. In better times she might even have been game to try for the hand of the Gryffindor Golden Boy, if only for the sport of it, but even hours later she still had not come to terms with the request coming from Lord Slytherin himself. Needing to seduce Harry Potter on pain of death sounded like the premise of a serial in Teen Witch Weekly (the kind that Tracey loved to read in History class), not the primary preoccupation of the heiress of a great House on the brink of war. And of course there was the start of her advanced NEWT-level classes, and the need to watch over Astoria… she could not afford to divert her attentions, noblesse oblige be cursed.

Perhaps the worst part of her whole predicament was that she could not share it with anyone, not even blood. Lord Slytherin had insisted on an unbreakable vow of secrecy – "I mean no discourtesy to the honour of your House, but honour alone will not suffice when fate itself hangs in the balance." On retrospect, this was not a disadvantage; it was not as though anyone would have believed her. There was refuge in audacity. Or absurdity. After worrying the house elves with several hours of oscillating between hysterical laughter and morose silence, Daphne fell asleep to troubled dreams.