He pointed to the disordered dining table. “If Qiao Guang was dead drunk, how did he get back to his own bed? Suppose he followed some basic instinct and stumbled his way to the headboard and lay down — how did his socks end up bunched at the soles of his feet?”

Only then did everyone notice: sure enough, Qiao Guang’s socks were piled at his arches.

“There is only one explanation.” Shi Ting’s gaze was deep and razor-sharp. “Someone entered Qiao Guang’s home and dragged him to his bed. Qiao Guang’s feet were dragged across the rough cement floor, and the friction naturally pushed his socks down to the soles.”

Bai Jin crouched down and lifted one of Qiao Guang’s feet. Sure enough, on the heel was a clear abrasion, the skin around it raw and torn open.

“The distance from the dining area to the bedroom isn’t that great. Why would his heels be injured this badly?” E’Yuan pushed up his glasses. He had focused entirely on the wound on Qiao Guang’s wrist and had never thought to look at the injuries on his feet.

Shi Ting said, “Qiao Guang stands about 170 centimeters and weighs roughly 65 kilograms. If you or I or any of us dragged him to the bedroom, his heels would not be damaged this severely. This can only mean the person who dragged him was small in stature and physically weak. It took a very long time for her to haul him to the bedroom, and the prolonged friction between Qiao Guang’s heels and the cement floor tore the skin completely open.”

Shi Ting’s gaze came to rest on Yan Qing. “I suspect the killer is very likely a woman — or possibly a child.”

That single sentence landed like a bolt from a clear sky, leaving everyone stunned and speechless.

“The likelihood of a child being the perpetrator is low. Killing four people one after another while orchestrating everything so meticulously — a child doesn’t possess that level of careful thinking or capacity for action. I lean more toward a female perpetrator.”

“Killing four people one after another?” Bai Jin murmured quietly to himself. “Does Seventh Brother mean that whoever killed Luo Baimei and Qiao Guang is the same person? But then why did the killer stop using Classroom 104, and why did the method change?”

“Figure it out yourself.” Shi Ting’s expression turned stern, his tone sharp.

Bai Jin looked to Yan Qing for help — he wasn’t sure when it had started, but he’d come to find the young Miss Yan of the Yan family remarkably dependable.

Yan Qing had no choice but to step in and spare Bai Jin.

“Because the killer wanted to bring her string of murders to a perfect close. Think about it: if Director Shi had not uncovered the killer’s entire scheme, what conclusion would you have drawn about Qiao Guang’s death?”

E’Yuan picked up the thread. “Suicide.”

“Why would Qiao Guang take his own life?”

“Suicide out of guilt — to escape justice.”

Yan Qing gave a small smile. “Qiao Guang killed three people — Leng Yu and the others — and then killed himself out of guilt. The case ties itself up neatly, while the real killer walks free. That is precisely the outcome she was ultimately after.”

When she finished, Yan Qing looked to Shi Ting. “I don’t know if I got that right.”

Shi Ting gave a single nod, his expression visibly softening — though when he turned back to Bai Jin, the sternness returned by a few degrees. “Take your people to Luofangzhai on Xinkou Street and find out whether a woman came in yesterday and bought all three items — the braised beef, the roasted chicken, and the pig’s head meat — at the same time. While you’re at it, check the nearby liquor shops and ask whether anyone purchased this brand of liquor.”

“Understood. I’ll head out right away.” Bai Jin put on his cap.

Shi Ting then called over the young police inspector who had been keeping watch downstairs the entire time.

“Yesterday evening — did anyone come through carrying food and wine?”

The young inspector thought carefully. “There are quite a few residents coming and going from this building. It was dinnertime, and many people were carrying food baskets.”

“Think again — was there a woman carrying wine bottles?”

The inspector scratched his head, and then his eyes suddenly brightened. “There was.”

—