MTL - The Roots of Manga - Chapter 3 lost legends

Infernal Demon Dragon: A dog like you dare to face me in combat? Do you wish to die so much?

Hakuto's life changes forever when his father Shin— a man with highly questionable morals—marries Kagura Kurotsuki, the CEO of a multinational company, and they move into her luxurious mansion.There, he meets the alluring daughters of his new stepmother: the seductive Yuzu—who doesn't hesitate to tease both her new stepbrother and her stepfather in ways that are... rather bold—and Rika, more introverted and irritable, yet just as sensual.But nothing is truly as it seems...Kagura is a succubus, but Rika and Yuzu are different.They were born from a demon and a vampire—something that shouldn’t be exsiste.Because of that, demons, vampires, even humans want them.But Hakuto won’t allow it.He’ll never let anyone hurt his beloved stepsisters.

Ukei Kaito fought a desperate struggle in order to fulfill his role as a summoned hero. He defeated the Demon Lord and saved the very world, only to meet an end filled but with betrayal. The companions that he’d trusted throughout his journey betrayed him and killed him by sticking a blade through his chest.

The notorious imperial court lackey and the meritorious military general were well-known for their mutual dislike, a pair of arch-enemies set in stone. Who could have foreseen the unexpected change in the winds of heaven: the general injured on the battlefield, both legs disabled, and even forced by the emperor to marry his nemesis.  

With one marriage edict, two people with mutual hostility are forced to marry and live under the same roof. Yet after these long days together, they come to the realization that this fellow is not truly devoid of any saving grace/unattainable and high out of reach.

- Description from Novelupdates