"Who swapped my brush for a foundation wand?" Qi Ji snapped, holding up the wrong tool so everyone could see. The students laughed. Someone shouted, "Professor, makeup or murder?" "Both," Qi Ji said and moved the wand like a scalpel. "Tell me how this changes the stroke." "Too soft," a woman in the front row said. "It smears." "It hides fibers," another student guessed. Qi Ji smiled and let the mockery land. He let it land and then took it back. "Watch," he said. "Pretend the smear is blood. Pretend the fibers are hair. Pretend the scene is deliberate tampering." He flicked the wand, dabbed fake blood from a demo tray, and dragged it across paper. He talked as he worked. "Smear like this ruins ridge detail. But the wand's soft head catches particles instead of pushing them aside. You can still recover a directional smear pattern if you change your lift angle." "You mean we can..." a student started. "You can," Qi Ji cut in. "But you do three things first." "Settle on the angle." "Use adhesive with lower tack." "Document the damage before you attempt any lift." He demonstrated the three steps in quick movements. The students leaned forward. "Professor," Director Han said from the back with a small clap. "Improvise your way out of being pranked." Qi Yue sat near the side wall, arms folded, watching more than listening. He raised an eyebrow and did not laugh. Qi Ji caught the look, and his jaw softened