I Become a Martial Arts God in the Chaotic Demon World - Chapter 29 - : Trading

After losing his parents to the apocalypse, Silas only wished for one thing. To awaken a powerful mutant ability and purge the earth of any iniquities. However, his dream was shattered when he failed to awaken any mutant ability on the day of the awakening. He was bullied by his peers. However, when all hopes were lost, Silas awakens a system. [Silas Griswold has met all requirements to become a host] [System binding... ] [To complete binding host needs to complete three quests] [Congratulations, you have completed all quests ] [System binded successfully] [Your evolution will now begin!]

The main character is reborn as a character from a game he played in his previous life. This character falls into ruin along with the villainess, spending the last of their years together. A man named Kururi Helan.

She is the underworld Ghost Doctor’s only disciple, who accidentally transmigrated into the body of the main wife’s daughter in the general’s mansion. She used to be a punching bag.Now, she stepped on her dregs of an older sister, put her father’s concubine in her place, and teaches any objectionable aristocratic ladies a lesson.

Her days are rather free and unfettered. But when did that cold as ice prince from the rumors, sporting a deadpan face all day long, fix his gaze on her?
He unexpectedly fawned and pandered to her like a devoted dog?

“Go away, you rotten man! Careful or I’ll needle you like a pin cushion!”

“Wife, why are you so fierce? As a husband, I’m so scared”
….the man is all smiles as he approached, his eyes gleaming with a cunning light.

- Description from Novelupdates

What happens when a man gets transported into a foreign world filled with magic?