My stepsisters are sexy demons, and I must protect them

«Dad, wake up! I finally turned twenty! What's that thing you were so eager to tell me about?» Vadim exclaims. He's a young man with hair as pale as milk and pale, glass-like eyes, waking Cassian at dawn with no hint of gentleness.

His voice betrays the impatience he can't quite hide.

After crossing the Vassisthar Desert, the natural border between the kingdoms of Elarval and Kristalia, Lilvyra leads Cassian to a remote and hidden place, hidden from the world's sight.

It is an ancient temple located deep within the Isilharan Mountains, carved deep into the rock. The temple, majestic and dark, is dedicated to the Primordial Shadow, Nyratalir, and at the center of that sanctuary an altar of polished black stone stands.

It is on that altar that Lilvyra gives birth to Vadim Thalukvar, just as she once did with Cassian and, before him, with their ancestors.

After giving birth to Cassian's son, Lilvyra built them a home identical to the one Cassian had grown up in.

However, after the events at the Sereltha Magic Academy, the Thalukvar family relocated their house to the kingdom of Kristalia, not far from Lumindor, the capital. The deaths of Eiric and Professor Gorakthal, along with the mysterious disappearance of Cassian and Lilvyra, inevitably drew suspicion toward them.

The royal guards of Elarval, under direct orders from the crown, searched every corner of the kingdom, but found nothing.

In the end, having fulfilled her duty, Lilvyra returned to reside within the pages of the Rithzargul, the dark grimoire that preserves her essence.

To prevent Vadim from suffering the same torment he once endured, Cassian enrolled his son in the Astralea Magic Academy in the kingdom of Kristalia, under a false name.

Free from the prejudice tied to his family name, Vadim became the most brilliant student the academy had ever seen, graduating with the highest marks in every subject and earning the respect and admiration of both students and professors.

He even managed to win seven of the ten semester tournaments he took part in.

Cassian has waited twenty long years — the exact time Lilvyra had told him to wait — for this day to come.

During that time, the feelings he held for her never faded. On the contrary, the passing years only strengthened them, intensifying the desire and love he feels for that being, both alluring and unsettling.

And now, that day has finally come.

The day he can finally see his beloved Lilvyra again — the being who changed his life forever, yet also made it whole.

Cassian hands his son a grimoire bound in pure black, open to one of its final pages.

It is a book Vadim knows well, though he has never truly understood its meaning. His father guards it with extreme care — almost with affection — but has never spoken of it openly.

For the past twenty years, each night before sleep, Cassian has devoted himself to reading that ancient and dark tome.

It is a ritual Vadim has observed since childhood, unaware that his father's devotion to that grimoire goes far beyond mere habit.

There was an even more distant past, a time when Cassian began reading the Rithzargul to keep his father's memory alive — ten years of silent reading to honor the man who raised him.

But as time passed, the reason behind those sleepless nights spent turning the pages of the grimoire changed. His thoughts now turn to someone who is not his father, yet has been just as important to him — Lilvyra.

«And now? What should I do?» Vadim asks, puzzled, still unaware of what is about to unfold before him.

The young man cannot even begin to imagine that this moment will mark the start of a path ordained by higher powers — a journey that will lead him to uncover a long-hidden truth about his lineage.

It will be up to that demon, Lilvyra, to awaken from the tome and guide Vadim's initiation into the Cult of the Primordial Shadow, as decreed on the day he turned twenty.

It is all part of a ritual handed down through countless generations — a blood pact that binds the Thalukvar family to the Primordial Shadow, Nyratalir.

For Cassian, however, things went differently. Having lost his father prematurely, his meeting with Lilvyra came earlier than the time and manner set by the ritual.

The awakening of Lilvyra, triggered by the power sealed within the tome, threw the entire process off balance.

But with Vadim, everything proceeded according to the ritual's timing and design. The wait of twenty years, the patient preparation — everything was carefully orchestrated so that Cassian's son may be welcomed as a full member of the cult.

Cassian tells his son to read aloud a sentence written in a language Vadim cannot understand.

Though increasingly confused, he obeys, his voice uncertain as he pronounces the words — a phrase that means: The daughter of Shadow awakens to raise her descendants.

The moment those words are spoken, Cassian is struck by a sudden sense of déjà vu.

A blinding light of pure darkness floods the room, followed by thick smoke pouring directly from the pages of the Rithzargul. His heart pounds harder than ever before, his lungs tighten as if caught in a vice, and his stomach twists as he watches the scene unfold before him.

He trembles with emotion and anticipation, gasping and nervously tapping his foot.

When the smoke clears, Cassian can't hold back his tears any longer.

At the center of the room stands Lilvyra, exactly as he last saw her twenty years ago. Nothing has changed — her curvaceous, irresistible body with gray skin, her wings black as night, and her goat-like horns, her imposing presence, and that cold, piercing gaze Cassian has fallen hopelessly in love with.

Seeing her again, unchanged from the image he has cherished so dearly for two decades, overwhelms him in a wave of emotion he can no longer contain.

Vadim, terrified and unable to believe what just happened, instinctively steps back to seek refuge behind his father.

«W-Who is that demon?» Vadim stammers, his voice trembling with fear. «A-And why, Dad... why are you crying now? What's happening?!»

Cassian, his tear-filled eyes soft with emotion, rests a hand on his son's shoulder, gently guiding him toward Lilvyra as he answers in a calm and tender voice.

«One day, you will understand too, my son,» Cassian murmurs, his gaze fixed on Lilvyra with a mix of devotion and nostalgia. «One day, you will understand why there are no women in the Thalukvar family.»

END SPIN-OFF