"Ying Chen isn't in the fourth-floor hallway. He's definitely hiding in one of the rooms. He's probably keeping an eye on his surroundings too."
"This guy doesn't play by the rules. His methods are bizarre. I need to be even more careful."
With Skirt Lady helping him along, Chen Ge reached the stairwell corner between the fourth and fifth floors. A faint stench hung in the air, and there were patches of moisture underfoot.
"Why did you suddenly stop?" Chen Ge whispered. He had been climbing upstairs, but Skirt Lady, who was holding his arm, had suddenly gone still.
Chen Ge couldn't see anything, but the moment he sensed Skirt Lady's abnormal behavior, he tensed up immediately.
He faintly caught the sound of a girl's singing — it seemed to come from a broken music box, intermittent and halting, the voice so eerie it defied description.
"Is someone coming? Get to the fifth floor — don't linger here!" A strong sense of foreboding washed over Chen Ge. He could tell the singing was coming from the fifth floor, and he was worried the sound would lure Ying Chen over.
"Someone just passed by on the fifth floor. Their footsteps made absolutely no sound." Skirt Lady's tone was strange. "Could I have been seeing things?"
"Wait — a music box? A girl's singing? A soundless figure? Could what you just saw actually be Ying Tong?" Chen Ge knew that in the real world, a broken music box sat on the table in Ying Tong's bedroom.
"Should we chase after them?" the woman asked.
"No, something's off." Chen Ge's grip on his backpack straps tightened. "If I were Ying Tong, I'd never let the music box make noise while fleeing. That would be practically screaming my location."
"It's also possible they accidentally bumped into the music box, causing it to suddenly start playing."
"I've been to Ying Chen's place. The music box was in Ying Tong's bedroom. If Ying Tong never went back home, then the person carrying that music box definitely isn't Ying Tong!" Cold sweat broke out across Chen Ge's body. "There's someone else in this building helping Ying Chen! They're carrying the music box around to draw attention! That bastard may have already figured out there are other people looking for Ying Tong!"
Ying Chen was clever, but Chen Ge was equally sharp. Both could pick up on the tiniest details.
"Do you know anyone in this building who's especially close to Ying Chen? Someone he'd trust unconditionally?"
"There are quite a few residents who get along well with Ying Chen. Oh, and Ying Chen is very popular with the children — they all love playing with him."
"Popular with children?"
"Mm-hm. Ying Chen has a wonderful personality. He loves playing games with the kids and sometimes buys them toys and candy."
"Was the figure that just passed by a child?"
"Sort of — very short, made no sound at all when walking. I almost thought I'd been seeing things." The woman let out a breath. She was also slowly realizing that the apartment building tonight was different from usual. "Are we still going to the sixth floor?"
"Of course we are. But keep an eye out when we pass through the fifth floor — see if anyone else is in the hallway." Chen Ge crouched down and felt the wet patches on the ground. "The water stains are almost dry. This doesn't look like water Ying Chen deliberately spilled to preserve footprints."
"You're being way too cautious. Maybe Aunt Wu just finished cleaning."
"How can you be sure it was Aunt Wu who cleaned?" Chen Ge heard a new name from the woman — Aunt Wu.
"She's the cleaning lady for our building. Very responsible — she mops the entire building every morning and evening." Skirt Lady said casually. "You're not suspecting Aunt Wu of helping Ying Chen, are you?"
Chen Ge said nothing, his mind occupied with something else.
Although the residential complex where Ying Chen and Ying Tong lived was run-down now, years ago it had been the most upscale neighborhood in the old city district. The fact that the building had been equipped with an elevator so early on made that clear.
Aunt Wu being in charge of cleaning the building wasn't anything unusual on its own. The problem was that she had also appeared in Ying Tong's World Behind the Door. This cleaning lady might already be dead in the real world, killed by Ying Tong — just like Skirt Lady and Wooden Man.
But there was another possibility: Aunt Wu might have done something to Ying Tong that left a deep impression on him.
Various guesses raced through Chen Ge's mind. Aunt Wu might have helped Ying Tong escape, or she could be the one feeding information to Ying Chen.
"What's the relationship between Aunt Wu and Ying Chen like?"
"Terrible. Aunt Wu is always arguing with Ying Chen. She hates cats — she thinks Ying Tong keeps bringing home filthy strays, which just adds to her workload." After a moment, the woman added, "Oh, and one time during a private conversation, Aunt Wu said Ying Chen had a sour, rancid smell about him, like cat meat left out for too long."
Chen Ge's mind raced as he pieced together the information he had. "This place was just cleaned, which means Aunt Wu was here before. Right after that, a short figure appeared carrying a music box. The music box was in Ying Chen's home. I'm guessing Ying Chen sent that short figure with the music box to test Aunt Wu — Ying Chen suspects the person who broke into his place was Aunt Wu!"
"I don't entirely follow, but what you're saying does sound pretty convincing." Skirt Lady had noticed that Chen Ge spoke with a certain logic — at least on the surface.
"Ying Chen doesn't know I exist. It's only natural he'd suspect Aunt Wu." The World Behind the Door was woven from Ying Tong's memories — the rules governing this world were Ying Tong's memories. If Ying Tong wanted to escape, the only tools at his disposal were the people and things within those memories. But on this particular day, Chen Ge had entered the World Behind the Door. He was the only anomaly.
While they'd been talking, they had already reached the fifth floor. The ground here was also slightly slippery — Aunt Wu had just cleaned it.
"There's nobody in the fifth-floor hallway. Shall we head to the sixth floor?"
"Don't rush. Look at the ground for footprints — look carefully." Chen Ge pressed his body flat against the wall. He had basically adapted to the darkness by now, having overcome that initial physical discomfort.
"Footprints?" The woman released Chen Ge's arm and seemed to step into the hallway to take a look. "There really are!"
"Keep your voice down. How many sets of footprints are there?"
"These footprints should be Aunt Wu's — she likes wearing cloth shoes. The other set of sandal prints probably belongs to a child in the building."
"Looks like our guess was right. Now check which direction the toes of the footprints are pointing — figure out where they went." Chen Ge couldn't see, so he had to rely on Skirt Lady.
"There are more of Aunt Wu's footprints. She seems to have lingered in front of the cleaning supply cabinet for quite a while — probably to grab her tools. The sandal prints, on the other hand, all head in one direction. Their owner was following right behind Aunt Wu." The woman added after a pause, "There's no one on the fifth floor now. Could they have gone up to the sixth?"
"Lingered near the cleaning supply cabinet? Normally, the janitorial supply room is on the first floor, isn't it? Wouldn't keeping cleaning tools on the fifth floor be really inconvenient?" Chen Ge recalled his previous visit to Ying Chen's place. As far as he remembered, there had been no cleaning cabinet on the fifth floor.
"The developer apparently wanted to build a model residential complex, so they had the property management install cleaning cabinets on every floor, stocked with daily cleaning supplies, plus ropes and firefighting equipment."
"That all sounds perfectly normal. But why would Aunt Wu specifically linger in front of this cleaning cabinet on the fifth floor?" Chen Ge gripped the woman's arm. "Was that cleaning cabinet locked?"
"No."