Watching the body fall from the building, the surrounding crowd didn't dare approach, clustering at a distance and whispering in hushed, terrified tones.
"Yukiko, you know how to drive, right?"
At Heiji's words, Yukiko nodded.
"Take my car and head back first. I'm probably going to be late."
"How are you going to get back later?"
"Officer Sakata will drive me."
Yukiko gave a quick nod, took the keys, and walked away with her long legs. She had zero interest in these kinds of cases; she'd seen more than enough of them in her time.
"Heiji, is that woman also your girlfriend?" Sakata asked curiously, glancing after her.
Heiji shot him a look. "Officer Sakata, shouldn't we keep our focus on the case?"
"Ah, right." Sakata gave an awkward laugh.
Heiji looked up toward the roof. The building was about seven stories high. On the rooftop, surrounded by a stainless steel railing, a large black bag was fluttering in the wind.
"Officer Sakata, go up to the roof and take a look."
Sakata hurried into the building and reached the top in record time. He called Heiji's cell phone from above.
"Heiji! The door was open, and there's a wire connected to it. The other end of the wire is hooked to a large black bag. There are two ropes on the ground, both tied to the railing. Ah—"
Suddenly, Sakata let out a sharp cry of pain. "There's a razor blade taped to the railing! Fortunately, it doesn't seem very sharp."
"A blade?" Heiji's mind raced. "Does the rooftop door open outward?"
"Exactly! Heiji, how did you know?" Sakata asked in surprise.
"It looks like someone was up there before you. Investigate immediately—find out who was on that roof in the minute before the body fell."
At Heiji's instruction, Sakata hung up immediately. Soon, the surrounding officers received their orders and began cordoning off the area with yellow tape.
Heiji furrowed his brow and turned his gaze toward the perimeter. He saw a woman whose face had turned bone-white; she stumbled back a few steps in horror before quickly getting into a car and speeding away.
[This plot... why does it feel so familiar?]
He had a faint feeling he had seen this play out in the anime before, but he couldn't quite pin down which specific incident it was.
The Deduction on the Streets
Sakata ran back down, dragging a middle-aged man along with him.
"Heiji, I found someone! This man appeared on the roof one minute before the incident."
"I was up there, but I'm not the killer! Someone called me and told me to go up!" the man explained, his voice trembling with panic.
"Someone called you?"
"Yes, it's true! I swear!" the man shouted.
"But appearing up there so sneakily is still highly suspicious," Sakata said sternly.
"I didn't kill anyone! I really didn't!" the man screamed in terror.
Heiji walked over to the corpse and examined it closely. "Officer Sakata, do you have any disposable gloves?"
He took the gloves Sakata handed over and pulled them on. He carefully peeled back the victim's collar and saw the bloodstains inside. His brow furrowed as he lifted the victim's hand and rotated it slightly; a stiff, clicking sound echoed.
"Officer Sakata, he's not the killer."
Sakata looked at Heiji in confusion.
"The blood at the wound has already coagulated, and the joints are no longer flexible. The time of death was over thirty minutes ago. This man, however, reeks of cooking oil—he's likely a resident of this building and was in the middle of making a meal. It's impossible for him to be the killer."
The middle-aged man stared at Heiji with wide eyes, looking utterly stunned.
"You're free to go," Heiji said, having no time to explain further to him.
"Heiji, what's the next step?" Sakata asked.
"The victim was knocked out with drugs first. Then, the killer used a small knife to strike a fatal blow through a wallet. Afterward, the body was brought to the roof, covered with that large black bag, and tied with a wire that was connected to the door."
"Wait, Heiji," Sakata frowned. "The weight of a corpse can't be supported by a single wire."
"Which is why there was a blunt blade on the railing."
A sharp light flashed in Heiji's eyes. "The body was first secured to the railing with two ropes. Then, a wire was tied to the black bag, with the other end pulled taut and fastened to the door."
"But because of those two ropes, the body wouldn't fall even if the door was opened," Sakata pressed.
"What if, when securing the body, it was lifted slightly higher? You use the blade to catch the position. As soon as the door opens, the wire pulls the bag, and the body drops down due to its own weight. Even if the blade isn't razor-sharp, a rope isn't that thick. Under the sudden pressure of a human body's weight, the rope snaps. And just like that, the body falls."
Sakata stared blankly at Heiji. "How could the killer be sure it would succeed?"
Heiji shook his head and gave a faint smile. "The killer didn't need it to succeed perfectly. He just needed someone to discover the body at that exact moment."
The Naniwa Connection
"To create an alibi?" Sakata's heart skipped a beat.
"Or, he's just playing with the police."
Heiji glanced at Sakata, keeping his expression neutral. Sakata showed no obvious reaction, looking down at the body with a solemn face. "Heiji, to be honest, this is the third murder case like this."
Heiji looked at him.
"Last week, the Toyonaka incident. A few days ago, the Hirakata incident. Both victims had a small knife driven through their hearts, passing through their wallets."
"Another serial murder case?"
Heiji covered his face and lowered his head in thought, a cold sneer forming at the corner of his mouth: So it's the Naniwa Serial Murder Case. The killer should be this Sakata Yusuke.
[However... framing the Black Organization. It looks like I'll have to destroy all the evidence first.]
"Officer Sakata, let's head back. My father and Superintendent Toyama should have more leads."
After arranging everything, Sakata drove Heiji back to the Osaka Police Headquarters.