MTL - Marvel: I Am the Man of Steel! - Chapter 586

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

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.

[MATURE CONTENT]Arella is an angel.Well, she used to be an angel. A real, bona fide, halo-wearing, wing-flapping celestial being. That was until one tiny whoopsie where she unfortunately burns a pair of wings at a banquet happens.Fine!There was more than one tiny whoopsie.Fast forward a few hours later, and Arella found herself booted from the pearly gates with nothing but her wings and an eviction notice.Her family called it a “vacation.” Ha! A vacation, in the human realm of all places!One hundred years later, Arella calls it her new life. Turns out, living among humans isn’t half bad—especially when you can turn invisibly smug at their lack of ability to fly. Early retirement has never been so blissful. That is, until the heavens smack her face with a message: Arella’s back on duty. And her new job? Marry. The. Demon. King.Wait, what?!Marrying the Demon King isn’t exactly on Arella’s bucket list, especially when demons and angels have been sworn enemies for eons. But orders are orders. So, off she goes, wings drooping and attitude cranked to full sass, to meet her new husband—a devilishly handsome demon who seems unnervingly smitten with her.Not to mention the heat that surges within her the moment she lays her eyes on him. Cue in dinner dates, fiery arguments (literally), and a series of catastrophes involving Arella purposefully setting a demon's hair ablaze with her holy fire.But as Arella settles into this bizarre celestial-demonic union, she uncovers a sinister plot that threatens not just her marriage but their entire reality. Turns out, angels and demons might have to join forces to stop a threat that neither side can handle alone. And Arella? She might just be the unexpected key to saving everyone.Armed with nothing but her quick wit, trusty angelic powers, and a painfully doting husband who may or may not leave her love notes carved into rock when she is angry, Arella must navigate battles, betrayals, and the occasional marital spat to protect their world. After all, nothing says “happily ever after” like saving existence itself, .... right?Right?One fallen angel. One absolutely smitten demon king. And a whole lot of chaos.