The exposure of their safe house was like a basin of icy water, dousing the small confidence they had just gained from the potion's success. Snape reacted swiftly and thoroughly. Almost on the very night the detection occurred, he used a complex counter-tracking spell to erase every trace in the laboratory that might have been marked, then packed up all the core equipment and materials—he had clearly prepared trunks treated with the Undetectable Extension Charm for precisely such situations.
"This place can't be used anymore." His voice was firm and decisive, carrying a resolve that allowed no argument. He did not even spare another glance for the room that had housed months of their secret research, as though it were merely an old cauldron about to be discarded.
Lin Yanqing did not object. He silently helped with the cleanup, putting away his own crude embroidery tools and materials. He could sense the surging anger and deeper vigilance beneath Snape's calm exterior—his private domain had been violated, touching upon his deepest taboo.
Their new base was an abandoned classroom at the end of a secluded corridor on the castle's fifth floor. Dust lay thick over everything, several tables and chairs with missing legs were piled in a corner, and the air carried a stale odor. Compared to the fully equipped, hidden, and comfortable Room of Requirement, this place was downright shabby. But Snape valued its inconspicuousness and its location away from the castle's main traffic routes.
"At least this place won't 'respond' to anyone's needs." He spoke coldly, waving his wand and using a Cleaning Charm to clear out a clean area before setting up basic anti-scrying and warning magic. His movements were swifter than before, carrying the ruthless edge of someone forced into a corner.
Lin Yanqing began helping arrange