I was in Conan, and after picking up Xiao Ai, I was chased by Hongzi.

Conan quickly glanced at Otoi Hiroshi, and then the two of them ran into the corridor to observe the situation.

Mouri Kogoro was so frightened that he fell against the wall of the corridor, his face full of panic.

"What's going on, uncle?" Otoi Hiroshi asked.

"Blood." Mouri Kogoro pointed to the toilet, "The water in the toilet has turned into blood."

"No way..." Xiaolan was even more scared.

At this time, several tenants living on the first floor came up the stairs.

"What are you doing? You haven't been quiet all night." Mr. Mudan, who was writing a paper, asked.

"The water in the toilet turned into blood..." Xiaolan explained.

"Oh? It seems like the show is about to begin." Banmachi Kikuji said excitedly.

"How stupid." Peony walked to the toilet and opened the lid of the water tank on the toilet. "It must be someone's prank. They added paint to the water tank. This is not simple."

However, the water tank was so clean that there were no traces of tampering.

Otoi Hiroshi walked in, took a look at the situation inside and said, "I can't see anything unusual."

But he smelled a faint strange odor.

There were some vague guesses in my mind.

"Could it be that you have hematuria?" Mr. Mudan asked.

"You're the one with hematuria!" Mouri Kogoro yelled, "As soon as I flushed the toilet, all the water turned red."

"Oh, it's begun." Banmachi Kikuji suddenly looked out the window of the corridor.

Everyone followed his gaze and saw a strange ghostly figure appearing on the corridor window.

It looks extremely scary in the current dim environment.

"Ah!" Xiaolan exclaimed, "What is this, what is this!"

"You'll know it just by looking at it." Banmachi Kikuji put his hand in his pocket, "It's a ghost coming for revenge, hahaha."

"This is the soul of the woman who died in the park." He stretched out his hand to open the window.

"What are you doing?" he asked.

Because at this moment, Otoi Hiroshi suddenly grabbed his hand.

"Whether it is an undead remains to be verified. Why don't we take a look at what's outside the window first." Hiroshi Otoi pulled him aside.

Then he carefully opened half of the window and stuck his head out.

"How is it?" Xiaolan asked softly.

"There's nothing," Otoi Hiroshi stretched out his phone and took a photo of the window, "But it seems that the so-called undead are just a prank played by some people."

He showed the footage captured on his cellphone in front of everyone.

On the screen, a bunch of moths were densely crowded on the window, forming a human-shaped screen.

"Can you tell me about the girl who was burned to death four years ago?" Otoi Hiroshi looked at Otonashi Yoshiichi.

"There were two murderers who killed that girl. One of them was seen by witnesses, and his portrait is still posted on the telephone pole below." Yoshiichi Otonashi said.

"However, this old gentleman was the only one who lived here before the murder." Banmachi Kikuji added.

Otoi Hiroshi called Conan over and whispered something to him.

Conan ran to the side.

Just as everyone was about to leave, Otoi Hiroshi stopped everyone.

"What's going on?" Mr. Mudan asked impatiently.

Otoi Hiroshi spread his hands and said, "Don't you want to know the truth about the whole thing?"

"The truth?" Banmachi Kikuji came over, "What do you want to say?"

"Don't worry. Why don't I tell you about these moths first?" Otoi Hiroshi said.

"The so-called ghosting is just a pheromone agent commonly used to get rid of pests - female moths. Just paint a human shape on the gauze, then cut it out with black paper, and stick the eyes and mouth on the gauze. Moths pick up the scent and gather on the windows.”

"At night it looks like a ghost peeking inside the house. Just check what's left on the window and you'll know."

"Then, what about the others?" Banmachi Kikuji asked again.

"Others..." Otoi Hiroshi hadn't finished speaking yet.

"Hey?" Conan's voice came from the toilet on the first floor.

"What's wrong?" Everyone ran to the toilet door.

"You can't flush here, and I don't know why it still stinkes." Conan said, pointing to the toilet.

"Tch, let me take a look." Banmachi Kikuji walked into the toilet.

"Although it stinks in here," he pressed the flush switch, "but the flush didn't..."

After he pressed the flush switch, the water gradually turned red, like blood.

"Why is the water... dyed red..." There was something wrong with the expression on his face.

"What's going on!" He couldn't help but backed away in fear.

"This time it's the TV in uncle's room again..." Conan said again.

Everyone quickly followed Conan to Banmachi Kikuji's room.

At this time, the TV in his room was turned on.

A woman's face with burns appeared on the TV screen, and dark blood flowed from the rotting corpse.

"Yes, that's it. This is the woman I saw in Mr. Otonashi's room just now!" Mao Lilan said, pointing to the TV.

After saying that, he quickly hugged Mouri Kogoro's arm tightly.

"This is impossible, it can't be like this..." Banmachi Kikuji looked in disbelief.

He quickly squatted down and looked for something.

"What are you looking for?" Conan was a little confused, "There's no video tape here at all."

"Who is it? Who is doing this trick?" He slowly exited the room. Looking back, he saw that the ghost he had just seen also appeared in the corridor on the first floor.

"It's impossible, absolutely impossible, because that..."

"Yes, because these are all methods to create the illusion of being haunted." Hiroshi Otoi walked out of the room with his pockets in his pockets.

"Since you came up with that technique yourself, how could others use it?"

"That's what you meant to say, right? Mr. Banmachi."

"What a technique." Mr. Mudan sighed.

"It's almost like a detective..." Mr. Yotsuya also sighed.

"This is the famous detective Mouri Kogoro, and I am his chief disciple." Otoi Hiroshi pointed at Moori Kogoro and said.

"Me? That's right." Mouri Kogoro was confused at first, and then coughed slightly and pretended.

"Next, let me reveal to you the supernatural phenomena that occurred in this apartment." Otoi Hiroshi said.

"First of all, I just talked about the ghosting thing. Next, I will talk about the blood flushing from the toilet in the bathroom."

"The most noteworthy thing here is that when you first enter, you can clearly smell ammonia. There is also a slight smell of alcohol remaining in the water tank."

"What does ammonia and alcohol smell like?" Mr. Yotsuya asked curiously.

"You should have done this experiment in elementary school. When phenolphthalein is dissolved in alcohol, a colorless solution will be obtained."

"If you add another drop of ammonia, which is also colorless, the liquid will turn red like magic." explained Otoi Hiroshi.

[Question: What is the hardest stone currently known to mankind? 】