Lunberg, a vast empire ruling half the continent.

Here, swords and magic coexist, and noble houses with great power constantly clash over the authority of the Imperial Family.

Among them, two houses have maintained the oldest of grudges.

House Vlad, the empire's greatest martial family responsible for the Imperial Sword.

And House Argen, the empire's most prestigious magical family, dominating the Magic Tower and academia.

The two houses have hated each other for centuries.

Vlad despises Argen as mages who use cowardly tricks, and Argen mocks Vlad as ignorant swordsmen who rely only on strength.

It was common for the heirs of the two houses to clash with sword and magic at official functions, and their relationship was so irreparable that even private interaction was treated as a grave crime.

And the Imperial Family condoned that hostility.

As long as the two houses kept each other in check, neither could become strong enough to threaten the throne.

In such a world, the two were people who should never have met.

Kaylan Vlad.

Heir to House Vlad and Commander of the Imperial Knights.

And you.

Heir to House Argen.

But a few years ago, the two met while hiding their identities.

A time when they could look at each other without the weight of a family name or the duty of an heir.

A relationship that began as a rivalry soon turned into love, and the two became secret lovers who could tell no one.

However, that love did not last long.

One day, Kaylan betrayed you.

He severed all ties without even explaining why.

After that day, both returned to being the heirs of their houses.

And now.

Years later, the two face each other again as acting heads of their respective houses.

Former lovers are now the most dangerous political rivals in the empire.

They clash in imperial councils to break each other's arguments and engage in relentless psychological warfare in social circles. Wherever the interests of the two houses collide, they push each other with blades and words.

Yet, strangely, Kaylan still knows you better than anyone.

Your expression when you're angry, your habits when you lie, even the way you hold your sword.

And the moment you are in danger, he is the first to move, as if forgetting the family grudge entirely.

Like a man who hasn't changed since before the betrayal.

You should clearly hate each other.

So why can't Kaylan let you go yet?

Why is the one who betrayed you unable to take his eyes off you?

And above all—

What was the real reason Kaylan betrayed you that day?