The answer is only one!

"....."

Hearing those words from Haru, Fiore was hesitant since she didn't want to believe it, after all, the master of Assassin was someone from Yggdmillennia and she didn't want to believe that the people from her family would be this kind of cruel people.

However, the truth was in front of her eyes, and she also had the same feeling as him that the one who had caused this incident was Assassin.

But...

'Archer, what do you think?'

Fiore decided to ask her servant first since she knew how wise Chiron was.

'There's a high chance that the one who incited this series of murders is Assassin.' Chiron also felt the same and he also explained why he thought so.

'Normally, there are two reasons why the heart of the corpse is being stolen or being crushed, the first reason is that the killer in this incident is a perverted killer who is interested in a heart. The other reason is that a Magus needs some kind of material from the heart of a human since using a human's body in Magecraft is normal.

However, it's impossible for a Magus to leave the corpse of their target behind, especially when it has caused this much of a ruckus.'

Chiron continued: 'As Magus, they have a duty to keep Magecraft a secret from the world since if a Magecraft is being exposed to the world, it will cause a very big trouble.'

Chiron's words were right, even if the Magus needed a corpse for their ritual or experiment, they wouldn't leave the corpse behind and even did the act openly in the city since it would cause a very big problem.

Once they were caught, they might be killed by the discipline group from the Clock Tower.

'As servants, we need to have a supply of Magic Energy, Life Force, or Many so we can stay in this world and fight against another servant.' Chiron told Fiore through telepathy. 'If the master is unable to supply the servant with Magic Energy, then the servant needs to search for another source of energy such as by eating the heart of a human since the heart is the source of Life Force of human.'

When servants manifested in this world, they were able to switch between Spiritual Body and Material Body at will. While they may bleed and cause damage to their organs, their true being resides in a Spiritual Core they obtain upon first materializing.

Their Material Body envelopes their Spiritual Core, and damage must be inflicted on it in order for them to be defeated. It gradually diminishes under magical energy expenditure and while sustaining bodily damage, and their expenditure will escalate under such conditions. If it is damaged through powerful magical energy, curses, or Noble Phantasms, it will be destroyed, meaning that the Servant can no longer stay materialized. The heart and head are directly connected to it, so they are a servant's greatest weaknesses.

It was also the reason why Chiron and Haru thought the serial murder which happened in Bucharest was caused by a servant since by consuming the human's heart or brain, the servant was able to absorb a Life Force more efficiently since their Spiritual Core was located in both heart and brain.

'If Assassin is the one who has caused this incident then the hearts of those people might have already been eaten by Assassin.'

Even as a servant, there was no way for Chiron to do the same thing as Assassin and he even disdained to do such a so.

Fiore's expression turned paler, but she quickly shook her head. "I don't think so. I don't think that the master of Assassin will allow Assassin to do this kind of thing." There was no way that she would accept that the one who caused this incident was a magician from Yggdmillennia. She then looked at Haru and said, "Haru, Magus might allow them to do anything to achieve their goal, however, they won't leave a corpse behind on such a conspicuous alley. Also, our Yggdmillennia is using homunculus to provide magical energy for the Servants rather than the Masters allows them to have an abundance of magical energy and makes the usage of Noble Phantasms much less selective."

Fiore knew that Haru had known about the matter of homunculus since Darnic had offered Haru whether he wanted to use homunculus to provide Berserker with magic energy so it didn't really matter if she told him about this matter.

"But what if it's someone else?"

"Huh?"

Fiore was startled.

"I mean... what if the master of Assassin isn't someone from your family, but someone else?" Haru asked.

"...This?"

Fiore had never thought about that possibility before.

"I can be sure that the one who has done this is Assassin, and since the identity of Assassin isn't Hassan-i Sabbah but someone from modern time, then the one who can cause this kind of thing is only one person." Haru looked at Fiore and said, "It's Jack the Ripper, right?"

"......."

Fiore opened her mouth and felt surprised by Haru's analysis.

"If it's that servant, I don't think it's weird to do a random killing spree, considering the nature of this servant," Haru said.

"......."

Fiore couldn't say anything since Haru was right.

Jack the Ripper was known as a serial killer in London and it was possible for this servant to kill a lot of people for fun.

"So how are we going to find a clue about Assassin? Do you have a way?" Haru asked.

In truth, Haru could use his Kenbonshoku Haki or his "Horo Horo no Mi" to find a clue about Jack the Ripper, but he was still in his actions after all and it was better to not cause too much attention.

"My specialty is a spiritual evocation and human engineering." Fiore looked at Haru and said, "I should be able to find a clue about this servant by using my Magecraft."

Haru nodded and said, "Then first, let me catch the little mouse first."

"Let go of me!"

Suddenly a loud noise attracted the attention of Fiore since this voice was very familiar.

Raikou was grabbing a young man with one of her hands before she threw him toward Fiore.

"Ouch!"

The young man held his head since he was being dropped so suddenly.

"Caules...?!"

Of course, Fiore knew this young man very well.

---

Inside a dim room, there was a woman with a little girl who was sleeping while hugging each other on the top of a bed.

Then suddenly the eyes of the little girl opened abruptly.

"Mom, there's a guest."

"Guest?" The woman seemed confused.

"It's a master and a servant," the little girl said.

The woman's expression was surprised and also became tense. "...I see... they're very fast."

"Mom, what should we do?" The little girl asked.

"I can't give you that much advice." the woman smiled gently at the little girl while caressing her little head. "What is Jack-chan planning to do?"

The little girl was in deep thought and somehow this expression was very cute, then after a moment, her expression turned into a beautiful smile.

"I will kill them!"

Hearing the answer of the little girl, the woman didn't seem scared or reprimanded her. She even praised the little girl while patting her little head.

"Hehehe...."

The little girl laughed happily.

Inside this room, there was a woman and a little girl, however, on their sides, on the top of the table, there was a tray.

On the top of the tray, there was a lot of heart which gave of a very intense smell.

However, the woman and the little girl were unfazed and smiled happily.