Caren Hortensia, a petite girl with silver hair and golden pupils.
Fair-skinned, with exquisite and cute features. As Kirei's daughter, Caren's mother committed suicide.
That's right. Due to her father's emotionless nature, and in an attempt to awaken some feeling in her husband, Caren's mother, who is already terminally ill, chose to kill herself in front of Kirei, hoping her beloved would possess normal human emotions, at least the emotion of grief.
In the original work, even watching his wife's death elicited no emotional fluctuation. Entrusting his daughter to the care of the Church, Kirei went to Fuyuki City and participated in the Fourth Holy Grail War.
In this world, the same events had occurred, but unlike the original work, Caren received different help.
"You are Caren Hortensia, correct? This is something my Master asked me to leave for you. He hopes... you can live well."
Watching the woman named Irisviel von Einzbern take out a drop of blood, the young Caren didn't yet understand its significance.
Due to her physical constitution, she was born with disabilities.
For example, the vision in her right eye was completely zero, and her sense of taste was almost nonexistent, among other things.
The only talent she possessed was called the 'Passive Sacrificial Medium' constitution, which was a... how to put it? A radar that could be understood as a demon detector.
Whenever a demon approached Caren, wounds would appear on her body.
Beyond that, Caren's body had another function: to engage in various forms of union with humans possessed by demons, then extract the demon and attach it to herself.
In the original work, due to her damaged emotions, she pathologically accepted her behavior bordering on that of a harlot and sacrificed everything for the so-called Church.
Even so, the Holy Church still cruelly treated her as a tool, not even granting her the most basic baptism.
In this world, she was found by Irisviel as a child and received Ryuya's blood.
Just like the blood Takatsuki Sen received, Ryuya's blood cured the disabilities in Caren's body and also healed her pathological constitution.
Having obtained a healthy body, logically, Caren's personality didn't change much.
She remained the seemingly taciturn but actually sharp-tongued girl, calm, cold, and she changed her faith.
"I once believed in my Lord, but you, Lord, would not help me. Since that's the case... I have found a new faith."
Initially, due to the Church's care, Caren believed her life was dedicated to the Lord, that she was one who served the Lord and the people loved by the Lord.
With strong conviction and faith, upon realizing the uselessness of her belief, the rapid transformation in her life made her understand what she truly should do.
"Lord, thank you for your help. I will live for you."
Another new day arrived. Following her usual routine, she offered a sincere blessing to Ryuya. Caren's work was still that of an Executor for the Holy Church.
But unlike usual, today she found the magical energy in her body surging strangely.
"This is..."
With the stinging pain on the back of her hand, looking at the existence known as the Command Spell, Caren understood. She had become a participant in the Holy Grail War.
And the Servant she summoned was actually...
"Well, I was following the scent of Ryuya, but it's just a little girl?"
Truly, not liking humans one bit, the Chains of Heaven had expected to see her husband, but Caren's presence left her somewhat disappointed.
Shaking her head, feeling these were but trivial matters, Enkidu expressed her desire to go to Snowfield City and participate in the Holy Grail War.
Hearing Enkidu's words, Caren also nodded.
Thus, they arrived in Snowfield City and encountered Kirei.
"Caren? I see. Have you come for revenge?"
The moment he saw Caren, he knew this was the daughter he had abandoned over a decade ago.
Her features, identical to her mother's, left a deep impression on Kirei. Thinking his daughter had come for revenge after gaining power, Kirei asked.
"Revenge? Are you joking, Kotomine Kirei?"
Her feelings towards Kirei were basically nonexistent, as she had never been cared for by this man.
In Caren's view, there was only one reason she sought out Kirei, and that was...
"Kotomine Kirei, the purpose of my visit has nothing to do with revenge. In your eyes, do you truly think I am someone so bored as to come seeking revenge from you?"
Her golden pupils coldly stared Kirei. Caren's words were clear: "I came to find you this time only to issue a warning, Kotomine Kirei. You are also a participant in this Holy Grail War, so do not entertain the thought of opposing my Lord."
"Otherwise... even if you are my biological father, I will still kill you, to clear all obstacles for my Lord."
Having stated the purpose of her visit, under Kirei's complex gaze, Caren and Enkidu left the Holy Church, leaving only the King of Heroes and Kirei.
"Pfft... Ha... Hahahaha..."
Not long after Caren and Enkidu left, a wanton smile suddenly appeared on Gilgamesh's previously serious face.
"Hahaha, Kotomine! To think you have a daughter. How amusing. This king has witnessed something most delightful today."
Finding the father-daughter relationship between Caren and Kirei very interesting, Gilgamesh expressed considerable amusement through his laughter.
"My relationship with my daughter? I rather think, King Gilgamesh, that you are happy to see Enkidu again."
"Although this Enkidu is not the Enkidu from your world, King Gilgamesh, being able to meet your dear friend from a parallel world is what makes you happiest, isn't it?"
"Hmm..." Normally, hearing such presumptuous words from Kirei would enrage Gilgamesh.
But after experiencing the previous Fourth Holy Grail War, witnessing Iskandar, Ryuya, and Artoria, also the Kingly path of the Female Gil, had changed him… he was no longer that Chuuni Golden King.
His originally rampant laughter gradually subsided. Gilgamesh, unusually, nodded and frankly admitted, "Kotomine, you are not wrong. This king is indeed happy to have seen my dear friend."
"Moreover, this king feels that many interesting events will occur in this Holy Grail War."
His crimson gaze turned towards Snowfield City. Gilgamesh seemed to sense some strange aura.
That... was precisely the King of the Gods who had once cursed Uruk, cursed Enkidu, causing him to lose everything.
The aura of Marduk!