A dark night street.
The streets of bubble-era Tokyo were a city of youth hitting the peak of entertainment. Even though it was nearing its end, true to the bubble, people flaunted luxury and went out to have fun with their partners by their side.
In an alleyway of such a city. A man was led into the alley by an enchanting woman who had seduced him.
Naturally, it was for *that* kind of business, and she had openly seduced him with her charms. The man was rich anyway and was confident that even if she was a "flower snake" (prostitute), it wouldn't be a problem.
As she proactively initiated a kiss first and things were heating up...
And so, the man died.
Her name was Hassan of the Serenity. A woman named Hassan who had abandoned her name, taking the name Zayd. A Hassan who still remembered her name and couldn't abandon it, full of lingering attachments, she herself thought she was a defective, disqualified failure compared to other Hassans.
Her skill alone was that of an assassin worthy of the Hassan name. A maiden made of a deadly poison that could even kill Phantasmal Species. While not Hydra-venom level, her bodily fluids, including her blood and saliva, boast the power of a C-rank Noble Phantasm capable of bringing down even a Servant.
Having confirmed that her Master, Jinga Seiji, was an unworthy lord for her, she was sustaining her manifestation by seducing men and performing soul absorption.
She had a wish. Just as other Hassans had wishes, even she, the leader of the fanatics who should have no wish, had a wish to find her ideal partner.
Some among the Hassans wished for their name to remain in history, others wished to have a single personality. She was searching for someone who could withstand her poison.
True to being the leader of the fanatical assassin group, the Hassans, she was not born with a body made of poison from the start. Her loyalty to the order was that strong, and she modified her own body because she wanted to become great as an assassin.
Just as all Hassans except for the last leader, Hassan of the White Mask, and Hassan of the Benefactor, who became a Hassan despite not being one, modified their bodies, even the first and last Hassan, the Old Man of the Mountain, was a human who had undergone body modification.
However, she regretted it. Even after ascending to the position of Hassan, she did not carve her face according to tradition, using the excuse of using her beauty for honey traps. She was afraid of that.
The 1st Hassan, Hassan of the Demon Arm, showed his piety by grafting the arm of the evil spirit Shaytan despite being ordinary, modifying his body to not eat food, and even carving his own face.
But she, in fear, ran from reality, saying she herself was unqualified to be a Hassan. Only at the moment of her death at the hands of the Old Man of the Mountain did she acknowledge that she had been a Hassan. She regretted making her body from poison. If that were known, the death knell would surely toll for her.
Hassan of the Serenity, nevertheless, knowing that fear, decided to continue the Holy Grail War by sacrificing innocent humans for her wish.
She had already killed several people to replenish her magical energy, and her murders had become a serial killing case called "Death's Merry." Of course, in Tokyo, a city of luxury and pleasure, it was a case only the police cared about.
Tonight, she set out to find another Master or Servant. Whether for the sake of the Grail, or to find her destined person...
"You've been making quite a spectacle, haven't you?"
"!?"
At that moment, she hurriedly turned around at the voice from behind, and a chain nail flew towards her. The Serenity quickly twisted her face to dodge, but even with her Agility A+, the swift strike couldn't be completely avoided, grazing the white skull mask she wore and shattering it.
Thud...
A mask with considerable defensive strength for a mask, one that even a Servant couldn't break with weak force. The Serenity realized they seriously intended to kill her. She immediately drew a dagger to respond, but...
"Your speed passes. Now, shall I test your senses?"
Cybele (Mystic Eyes of Petrification)
"Ugh!?"
The moment she met her gaze, it was already over. No, even without meeting her gaze, her Mystic Eyes turn everything to stone. The corpse of the man she killed earlier turned to stone, and even the Serenity, who has resistance as a Servant, began to slowly turn to stone starting from her legs and hands.
"Your senses aren't great. Or, did you notice but react too late?"
"A Servant..."
"It doesn't matter. Now, shall I test your mental strength?"
"What is this... If you want to kill me, kill me quickly."
The Serenity aimed for a mutual kill as a Hassan, at the very least. If she delivered a killing blow, the Serenity thought of leaping forward instead, having her body pierced and melting her with her own blood. But... all the other woman did was remove her glasses.
If earlier she just glanced down and looked... This time, she removed her seal and activated her Noble Phantasm.
"{Breaker Gorgon}(Self-Seal Dark Temple)"
Keeeeng...!
"!?"
{Breaker Gorgon}(Self-Seal Dark Temple). Usually, it is a seal that binds her own Mystic Eyes and demonic nature. However, by using it on another, it becomes a mental-type Noble Phantasm.
It activates just by pouring magical energy into the opponent and looking at them, simultaneously sealing the opponent's consciousness (soul) within Medusa's heart and allowing her to dominate them. Those with low or no Magic Resistance cannot even realize they are being affected, let alone resist.
A Noble Phantasm that cannot be blocked by strong willpower alone without a skill or Noble Phantasm that interferes with mental interference. A Noble Phantasm that can show the opponent various dreams like nightmares, erotic dreams, and even steal magical energy.
Originally, she needed to use another Noble Phantasm, {Blood Fort Andromeda}(Other-Seal Blood-Soaked Temple), to seal the soul, but being half a goddess now, one was enough.
Hassan of the Serenity went limp, becoming Medusa's puppet. She tried moving the body at her will.
"... Indeed, is this possible?"
True to being a goddess and monster, she could easily control the Serenity's body and even speak. Having rarely used it on others, it was the first time she used this Noble Phantasm on a Servant.
"I wondered what you were going to do, saying you'd go first... Why are you filming a body-snatching scene?"
"Is there a problem?"
"Isn't this the best subduing method?"
"Hearing you two talk is really weird..."
Fergus followed behind and arrived, Medusa spoke first with her own body, then continued speaking with the Serenity's body. Since the Rider version could shed her skin and create doppelgängers, she could naturally handle multiple bodies.
"When I said to just stop and persuade her, you go and do a body-snatch... An invasion of the Body Snatchers?"
"Weren't you going to add her to your harem anyway?"
"No... That, that may be true... but you know it's not intentional, right?"
"To try and put me in your harem... I'm rather pleased."
"Let's not say that with the Serenity's body..."
""Hehe.""
Fergus slapped his forehead and sighed. He had just finished reading a fairy tale to Manaka because she asked him to, and now he had a headache because of what Medusa, who went ahead, had done. Also, he had nothing to say because what she said was fact.
"I know. As a Heroic Spirit God who manifested, you want to help the Servants of the Holy Grail War rather than engage in slaughter, as much as possible."
"So, isn't that the only method? Fergus."
"It's confusing when you talk with the Serenity's body, so stop... You know what kind of being the Serenity is because I told you. She only has me. I'm immune not just to Hydra's poison, but even to the greatest poison on earth, Vashumna's poison. No, I should say resistant to Vashumna. So for the Serenity, I'm the only one."
"It's ultimately your sexual desire to hold the Serenity, isn't it?"
"Lord Fergus... do you want to impregnate me...?"
"................."
Fergus frowned and glared at Medusa and the Serenity (Medusa), and the two giggled while looking at him.
"It's half true, isn't it?"
"(Flinches)"
"Gods are originally prone to strong sexual desires. Especially heroic spirits who are gods. Hercules was like that too, right?"
"I know that..."
The senior heroic spirit god, Hercules. He once had sex with 50 princesses of a nation, one per day in rotation, as a reward for some deed, and also had a boyfriend attendant, Hylas, etc. Being Zeus's son, his sex life was promiscuous... Actually, gods tend to have strong sexual desires.
Mesopotamia's Ishtar goes without saying, and Ereshkigal also had sex for 6 nights and 7 days and still wanted more... Gods were just highly sexual from the start.
On top of that, though limited to his wives, once he started, his sexual desire knew no end, annihilating his wives... from Scáthach and the supreme goddess The Morrígan to the born trollop Medb and even the dragonkin Artoria, it was the epitome of peerless prowess. Because of such factors, his wives, beyond being okay with other wives being added because he would still love them, were also thinking they needed more people because the nights were too strenuous.
"But saying it like that makes me sound like a pervert."
"You're not trash like Zeus, so isn't that fine? You didn't kill a subordinate and steal his wife out of lust like David. Isn't this level of teasing light?"
"... Am I the overly serious one? You're good at gaslighting, huh?"
"I learned from you."
"Hmm... For now, let's take the Serenity. We'll talk about that later... Manaka is still in a stabilization period. It's not completely stable, so let's talk after everything's over. You know I don't lie, right?"
"...."
"... Right, there was that time I killed Shinji. I was insane then. I'm sane now, right?"
"I didn't say anything, but you seem guilty. It's fine. Just..."
"I think you're cute when you're being teased."
"When we get home, I'm giving the Serenity's body back immediately."
"Yeah yeah~ Sure~"
Medusa speaking nonchalantly in the Serenity's form. Fergus was slightly regretting having brought Medusa along for no reason...