I Breathe Euro - Chapter 30: The Little Angry Angel.

When the Terminally Ill Noble Allenbert woke up from his fever, he realized that he was the reincarnation of Karzan, the mad dog who roamed the underworld.…But something about this place doesn’t feel right.“Allenbert, nobles need secrets and darkness.”The sinister and chilling schemes of his brother, like a snake, are suffocating him from all sides.“You’ve been causing quite a stir lately.”The powerful and authoritative eyes and ears of the head of the family are hidden everywhere, watching him.“…When will I see Mother?”Meeting his mother, who has secluded herself due to a mental illness, seems impossible.“But it’s okay.”Karzan failed, but Allenbert’s journey is just beginning.“Two lives, two revenges.”There’s no mercy.I’ll pay back with interest, and make sure it’s done properly.

“Master, the people from the Zhuang family have come to cancel the engagement.”

“My fiancé whose beauty was said to be capable of causing the downfall of a city, finally decided to throw me away?”

“I think so.”

“I want to see this legendary beauty, and confirm whether this bastard is as really great as people said to have no flaws in all 360 degree, a picturesque appearance however you see him; does he need me to help him open the corner of his eyes (Epicanthoplasty) or reshape his chin (Genioplasty)?”

“Actually, he didn’t come.”

“He didn’t? He didn’t even come to cancel the engagement? What a wicked b***h.”

“He definitely will get karma.”

- Description from Novelupdates

In the fantasy world ruled by Matriarchy, Kael of the Ancient Moonstone House, was working as a guild receptionist. Throughout his life, he was protected by his mother and later, younger sister, who was considered one of the highest potential individuals in the Queendom of Elyria. One day, he hears that his sister has gone missing and his family has accumulated debts of over 127 million gold coins to the Bank. The Queen comes to his rescue, paying off his debts and in exchange, he has to marry her five daughters, who each excel in a domain of their own.Having the five imperial princesses and the Queen herself as the backing, Kael has become one of the most protected individuals in the Queendom. Little did his wives know that Kael had another identity. He is the most dreaded yet noble Assassin of the imperial city, “K,” one who hunts down the criminals who escape punishment either because of insufficient evidence or using their connections.Follow Kael's journey, as he navigates his life as the protected figure in the light and protector of justice in the shadows.

You thought being reincarnated as an extra-side character was bad? Imagine being thrown into the body of a villain who is disowned by his own family and discarded by the author.