Kuroitsuki

Xion Aijawa thought his life was finally coming together. That is, until he tried saving a cat stuck in a tree, fell into a pit, and... died

In his disoriented sate of "Freshly dead" the silly Xion accepted a strange request and ended up transmigrating into the world full of dungeons and Mana. 

He became illegitimate child of Marquis family hated by his three siblings.

According to the memory of the original owner of the body, Xion only had a month to live.

So, taking the cover of the banquet, Xion ran away. Aided by a mysterious Mall System, he makes his way to the distant borderlands, hoping to put his past behind him. 

But fate has other plans-. Xion ends up saving Darius Rael Darkhelm, the feared Archduke of the North, notorious for his ruthless and deranged nature. 

The silly Xion tried to run away but...

 Xion's heart thumped loudly as Darius effortlessly pinned his wrists using only one hand.

"I've heard you tried to run away."

Darius gently caressed Xion's pale cheek, "That must be a lie... After all, I've given you things even the royal family can't have. Isn't that right, my dear healer?" 

Xion gulped when Darius's thumb brushed his lower lip as a chilling smirk remained on his handsome face.

 "I-I think I should leave, Your Grace. I've overstayed my welcome..."

The room grew cold, and struggling Xion shivered.

 Darius's green eyes dimmed before lighting up with a dangerous glint. 

Xion felt a pit growing in his stomach when he saw the deranged archduke smile. Darius never smiled. And whenever he did, it only meant trouble.

"You're right," Darius said calmly. "So, let's get married."

Xion "...!!!!"
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This book will lean toward dark romance, but there will be no r@pe. This author doesn't like glorifying SA as romance.

[BL] Accidentally Becoming the Healer of the Deranged Archduke

Even after spending all night learning about Mana problems, Xion did not get even a glimpse of Moon Affliction.

He was suddenly glad that he had sneaked into Marquis Roberto's library in the middle of the night. If not for that, he would have no idea this strange disease even existed.

Affliction, as the name suggests, was the occurrence of pain. According to Allen, ancient people believed it was related to Goddess Myrtia.

Because she was the deity of light, this disease could only hide under the dark night. Its unpredictable changes, just like the ever-changing phases of the moon, earned it the name Moon Affliction.

Xion heard it just for the sake of hearing it. There was no useful information, and after knowing about the Devil's spawn, he was even less likely to believe anything.

Darius was lazily leaning on the comfortable couch like a king. He had been curious how Xion would react now. "It's not a disease, little healer. It's a curse."

The Unruly Healer Pushed Archduke to Bed