Chapter 8

As soon as they entered the cafeteria, the mixed smells of all the dishes blended together — not exactly pleasant.

The two found an empty table. Jiang Xuzhou sat down to wait, and before long Ruan Mingxi returned carrying two trays of food.

As expected, Jiang Xuzhou’s tray was filled with the things he liked. Even without ordering for himself, he never had to worry about finding something he disliked on his plate.

“The cafeteria food is heavy on oil and salt. Just eat a little to fill up. I’ve ordered another meal for you that’ll arrive later,” Ruan Mingxi said.

Jiang Xuzhou gave a quiet “mm” in response, scooping up a ladle of egg-drop soup with seaweed — though he couldn’t find the two strips of seaweed floating in it.

After swallowing his mouthful of food, Ruan Mingxi asked, “Where did you come from this morning?”

Jiang Xuzhou fell silent.

Late or not, the question had finally arrived — and it was unavoidable.

“Would you believe me if I said I was wearing gloves to clean the house?” Jiang Xuzhou asked with an earnest look.

Ruan Mingxi’s expression froze, clearly saying, Do I look like an idiot to you?

Jiang Xuzhou chuckled softly. “The professor gave me an old case file as material. I was running a mock evidence analysis — just for practice.”

Ruan Mingxi raised his eyebrows but didn’t press further. Jiang Xuzhou had done research projects before, and he knew what Jiang Xuzhou looked like when he was working on them. He accepted the explanation.

The 8•25 school bus case from eight years ago was tangled and complex. If the answers were easy to find, the killer wouldn’t still be unidentified.

Jiang Xuzhou didn’t want Ruan Mingxi to know he was investigating that case — or at least not so soon.

Given his sensitive position, digging into an old, unsolved case without authorization could cause unnecessary trouble if the higher-ups found out.

Jiang Xuzhou skillfully steered the conversation away.

When Ying Shi finished his tasks and came to the cafeteria, he saw that Ruan Mingxi and Jiang Xuzhou were still there, so he quickly carried his tray over.

“Captain, we ran a preliminary test on the mark under the desk. It showed a blood reaction — the underside of the desktop is smeared with blood,” Ying Shi reported, shoveling food into his mouth as he spoke.

On the way back to the bureau, Ying Shi learned from Ruan Mingxi that Jiang Xuzhou was a student of Professor Wei Wenshan.

Professor Wei was a specially appointed expert for the provincial department, often assisting with difficult cases.

Since Jiang Xuzhou was his student, and also the first to notice something was wrong with Yan Zhan — even accompanying Professor Yan to report it — Ying Shi naturally began to see Jiang Xuzhou as part of their own circle.

Ruan Mingxi did not hide the details of the case from him, and naturally stood on the same side as his superior.

Ruan Mingxi said, “The desks at Jinghai No. 1 High aren’t the lightweight plastic kind that are easy to move. As long as they’re not badly damaged, they’re never replaced. So if the blood under the desktop isn’t Yan Zhan’s, it might have been left there by a student from the previous year.”

Ying Shi swallowed his food with a sip of soup and replied, “That does make sense. After all, the underside of a desk is a blind spot. Normally, no one would bother to check for dirt there, so it’s perfectly normal that it went unnoticed.”

“No,” Jiang Xuzhou said firmly, immediately drawing both of their attention.

“You know something? Why are you so certain?” Ruan Mingxi asked.

Jiang Xuzhou set down his soup ladle. “Two reasons. First, Professor Yan once said that Yan Zhan was extremely meticulous and very clean. The simplest proof was his habit of repeatedly cleaning objects and constantly rearranging whatever was in front of him.”

　　“Isn’t that obsessive-compulsive disorder?” Ying Shi’s hand holding the chopsticks paused mid-air.

No sooner had he spoken than he suddenly realized: “Wait — are you saying Yan Zhan might have a mental illness?”

He thought of the textbooks they had packed up earlier, filled with excessive scratches, some pages even smeared with unknown substances.

Calling them a complete mess wouldn’t be an exaggeration. If there were psychological issues involved, those marks could be explained that way.

Ruan Mingxi frowned. “OCD is a neurological condition, but it doesn’t really fall under the category of mental illness, does it?”

They weren’t experts in this field, so they couldn’t give a definitive answer.

Jiang Xuzhou explained: “Obsessive-compulsive disorder is a type of anxiety-related neurological condition. It’s essentially the conflict of two conscious compulsions existing at the same time. Patients know their behavior is irrational, yet they cannot stop repeating it. The more they try to control it, the more painful and tense they feel, and the urge to perform the compulsive act keeps repeating in their mind.”

“As for whether Yan Zhan truly had OCD, that can’t be confirmed yet. But according to Professor Yan, Yan Zhan was a child with a strong sense of personal territory. His books were always arranged neatly, and his desk area was kept spotless. For him to leave the underside of the desk untouched is completely out of character.”

Jiang Xuzhou looked at Ruan Mingxi. Their eyes met, and without words, they both understood.

If it had been another child with a more careless personality, overlooking the cleanliness of the underside of the desk would have been perfectly normal.

For someone like Yan Zhan, who was obsessed with cleanliness and order, arranging everything neatly and repeatedly, leaving the underside of the desk dirty was completely out of character.

Ruan Mingxi pressed further: “If Yan Zhan really did have OCD, what kind of symptoms might he show? Could he attack others or harm himself?”

Jiang Xuzhou nodded. “It’s possible. In severe cases of OCD, during an episode, a person might lose control and end up hurting others or themselves.”

Hearing this, Ruan Mingxi immediately pulled out his phone and called a colleague in the forensic department. “Run the blood sample tests as soon as possible. Call me the moment you have results.”

On the other end, the colleague was momentarily stunned. They had brought back a lot of items, still unsorted, and hadn’t expected Ruan Mingxi to suddenly demand blood test results.

Once they recovered, the colleague quickly gave a firm confirmation.

“I’m going to Professor Yan’s house this afternoon. Are you heading home or coming with me?” Ruan Mingxi asked.

“I’ll go with you,” Jiang Xuzhou replied.

Ruan Mingxi smiled, clearly pleased. “Thanks for making the trip.”

Jiang Xuzhou smirked, used to his playful antics. “Where’s my delivery? It still hasn’t arrived.”

“Oh, I got caught up talking just now. It’s been delivered — you’ll have to bear with me a little longer,” Ruan Mingxi said as he tidied up his tray.

Ying Shi’s mouth twitched, his expression saying he couldn’t bear to watch his captain’s antics.

After Ruan Mingxi left the cafeteria, Ying Shi gave an awkward laugh. “Our captain isn’t usually like this. Don’t worry. He may not look like a good guy, but he really is one.”

　　Ying Shi’s gaze was complicated; when he looked at Jiang Xuzhou, it carried sympathy and guilt — “mixed feelings” would be an understatement.

Jiang Xuzhou was amused by his description; in fact, it was surprisingly accurate.

Ying Shi probably thought Jiang Xuzhou and Ruan Mingxi had only just met, and that Jiang Xuzhou was being used as free labor, which made him feel a bit guilty.

Ruan Mingxi was handsome, but in a way that made people think at first glance: this guy looks like a heartless player who tricks people. His good looks had a deceptive quality.

And when he wasn’t wearing a stern expression, his smile carried a roguish edge. Without the uniform, it was hard to believe he was actually a police officer.