Yan Junxun hoped Shi Shanyan could sniff out the key scent like a police dog, but Shi Shanyan had no interest in cooperating. The way he scrutinized the photos was as if he were browsing a photography exhibition, ready to give an impromptu critique at any moment.

Most of the photos Liu Xincheng took were of sexual assault victims from 2156. Unlike the ones cut out from newspapers on the urinal wall, these photos were clearer, documenting the victims' suffering from various angles. In the far corner, there were also a few blurry photos of the victims from behind, which must have been secretly taken by Liu Xincheng after his release from prison.

Yan Junxun saw that the transparent tape holding the photos had turned yellow, the crevices were filled with dust, and there were even cobwebs in the corners.

"He's proud of this," Shi Shanyan said, pushing aside the curtains with his finger. "He's showing off his badges to everyone who enters his territory."

Yan Junxun bent down, staring at the photos.

Shi Shanyan also leaned over and asked, "What are you thinking?"

"The killer has been here." Yan Junxun's speech slowed when he was thinking, breaking down all the captured information as if solving a problem. "He has a strong presence here."

The most jarring thing about the room was that it didn't look like a place Liu Xincheng lived in at all. It was as if he only owned the window and the bathroom in this room. The floor was clean, the stovetop was clean, and even the garbage bag in the trash can had been taken away, indicating that the killer was very careful about cleaning up his traces. But he hadn't touched the bathroom or the window.

Yan Junxun straightened up. "I need to see all the rooms."

......

The environment of Puli Residential Community was much better than Huihe Residential Community. Although they were also old-style buildings, they weren't dilapidated overall. The buildings were arranged very neatly. To give them a more futuristic look, glass was used to decorate the exterior walls during construction, so the community's property management fees were relatively high. There was a row of commercial shops at the entrance. There was no dedicated parking lot, so Yan Junxun had trouble parking his car and had to drive around a whole street to find a spot.

"I thought you were going to observe the photos," Shi Shanyan said before getting out of the car.

"I need the atmosphere," Yan Junxun looked at him. "Sharing a room with a pervert is conducive to my thinking."

"Impressive," Shi Shanyan pulled open the car door and gave Yan Junxun a sudden smile. "I mean, a pervert like me."

Yan Junxun and the pervert entered the residential community. The living environment here was even better than Yan Junxun's. There were even vibrant green belts on both sides of the sidewalk, although they were all digital projections.

The second victim, Li Jianhua, lived in Building Eight, and he had even chosen the eighth floor.

The elevator was a bit old and would shake slightly as it ascended. When the doors opened, the first thing that came into view was a brand-new mountain bike. It was leaning against the door, with a pair of washed, old sneakers hanging from the crossbar. To the left was the emergency exit. When Shi Shanyan stepped out of the elevator, he saw that the door to the emergency exit was open.

Yan Junxun entered the door code, and amidst a soft "Welcome home," he saw the situation inside.

Li Jianhua was 45 years old. In 2151, he was an old rail crew member in the Docking Area and was sentenced to seven years for repeatedly sexually assaulting female crew members on the same rail line. After his release, he moved to Puli Residential Community and insisted on freeloading off his elderly parents. In recent years, he had a record of stalking, indecency, and other misconduct.

"Dad," the indoor system's voice was very childlike, "the indoor thermostat has been turned on for you. I hope you have a pleasant time at home."

Li Jianhua's indoor system was a previous-generation system from the Docking Area prison. It was good at detecting human moods, but its self-adjustment range was small; it could only change its voice and tone, had no virtual projection function, and its core directive was to completely obey its master's commands.

The curtains in Li Jianhua's home were also drawn, but the window was open, and there was a scent of air freshener in the room. A lucky cat was placed on the coffee table in front of the sofa, and the corners of the tablecloth were neatly aligned. The bedroom door was not closed, the bed was also neat, and all the storage boxes were dutifully in their original places.

Fifteen years ago, news reports on the sexual assault case stated that Li Jianhua had a sex addiction. His parents had tried to help him correct this problem back in his teens, but at the time, the Docking Area promoted treatment with anti-hormone drugs, such as using large amounts of diethylstilbestrol to reduce libido. Long-term use would lead to an inability to ejaculate. This method is now called chemical castration. His parents therefore chose to seek help from a psychologist, hoping to solve Li Jianhua's problem through psychotherapy, but the effect was not good.

Before the sexual assault case fifteen years ago, Li Jianhua had repeatedly molested passengers on the old rail line, sexually harassing the victims through masturbation. He seemed unable to control his behavior. When he wasn't living alone, he even needed his parents to wash his feet for him.

"Dad," the indoor system's light screen automatically lit up, "the video update is complete. Preparing surround sound for you..."

"Halt system autonomy," Yan Junxun turned back from the bedroom doorway. "Turn off the illegal videos."

The indoor system fell silent for two seconds, then switched to a female announcer's voice: "Okay, Dad."

As the voice faded, the light screen disappeared, and the entire room went dark. The air conditioner and all other appliances turned off.

"Sexual assault news in the Docking Area is dedicated to leaking the personal information of both parties." Shi Shanyan tapped the fish tank on the side of the bar with a bent finger, which lit up at his touch. "Li Jianhua's video library also has photos of the sexual assault victims."

The light screen was only on for three seconds in total. Hidden within Li Jianhua's densely packed video library were news photos of the sexual assault victims, their names flashing by in an instant. But Shi Shanyan still saw them. Such visual memory and information-capturing ability were a rarity even in the Black Panther.

"There's a reporter with a keen nose for this kind of news who likes to fill pages with lots of photos." Yan Junxun sniffed the air in the bedroom. "He's recently shifted his focus to murder cases."

"Have you been photographed?"

"No," Yan Junxun felt the room was a bit hot, so much so that he unscrewed his bottle cap again. "A nameless detective doesn't show his face." He looked at Shi Shanyan again before drinking. "Please take care of your own privacy."

"I like being in the news." The colored light from the fish tank deepened the shadow on the bridge of Shi Shanyan's nose. He watched the goldfish swimming back and forth. "Being targeted by a sniper makes me feel immense joy."

Yan Junxun took a sip of water and said, "Oh."

......

Li Jianhua's disappearance was similar to Liu Xincheng's. Starting from the night of April 17th, his motley crew of friends couldn't contact him. It wasn't until a week later, when the property management found that the drainage ditch in Puli Residential Community was blocked, that a few pieces of him were found. The house currently belongs to his father, who lives in a nursing home.

Li Jianhua had no job and had been living off his parents' pensions since his release from prison. He couldn't take care of himself in daily life. Like Liu Xincheng, he would never take the initiative to clean. People are creatures of habit; as long as he lived here every day, he would leave behind a large number of personal traces. Yet, Yan Junxun couldn't find any personal traces of Li Jianhua in this room. It was as clean as a model home, with floors so shiny they reflected light.

It was as if "Li Jianhua" had been wiped away.

Yan Junxun felt the killer had been in this room too, but unlike with Liu Xincheng, he hadn't neglected any corner in Li Jianhua's room. He liked the environment here and arranged it according to his own preferences.

"The killer isn't scared at all," Yan Junxun looked at the fish tank. "He came to feed the fish."

"People always have a few friends," Shi Shanyan stopped playing with the fish tank light and said, "Even man-children do."

"If a good friend remembered your fish," Yan Junxun said mercilessly, "they wouldn't have let you clog up a drainage ditch for a week."

Yan Junxun was very concerned about the door locks. In both Liu Xincheng's and Li Jianhua's homes, the locks were intact.

Yan Junxun pushed aside the curtains and looked out the window. It directly faced the glass wall of another building. The afterglow of dusk was projected onto it, refracting a brilliant light. The community's property management was doing a good job, trying its best to maintain the glamour of the old district, even wiping the dust off the glass promptly, making it look clearer than the light screens on the street. The floors of the buildings were aligned in a straight line, and there were landscape lights at night. No one could have climbed in through the window.

"The killer walked in," Yan Junxun was dazzled by the light and said with a frown, "He had the key and the code."

......

As the two of them came out of Li Jianhua's home, they happened to run into the couple from next door coming home from work. Their gazes scanned over them, and they gave Yan Junxun a polite nod.

The man asked, "Going down?"

"Thanks," Yan Junxun said, carrying the empty water bottle. "To the parking lot."

The man pressed the elevator button for Yan Junxun, his gaze involuntarily drifting to the Restraint Lock on Shi Shanyan's wrists.

Shi Shanyan raised his hands, and the Restraint Lock slid down to his sturdy forearms. He said to the man, "It's a toy. Pretty realistic, right?"

"Ah." The man didn't know how to respond and just nodded with an awkward smile.

Shi Shanyan pulled his arms apart. The magnetic strip between the Restraint Lock sounded an alarm, and a current immediately zapped him a few times, preventing him from pulling further. He said regretfully, "I don't recommend you play with this."

Yan Junxun had already stepped into the elevator. He pushed back the black hair falling over his forehead with one hand, partially covering his eyes, and grabbed Shi Shanyan's forearm with the other, pulling him into the elevator.

"Sharing the fun," Shi Shanyan stood next to Yan Junxun and waved at the man. "Bye."

The elevator doors closed with a "ding," and the elevator began to descend.

Shi Shanyan leaned his body toward Yan Junxun and asked sincerely, "Do you have any sexual fetishes?"