The supporting character's harem is very normal - Chapter 474 Peace before the Storm

The mysterious boy Ling Chen is saved by a little girl as he lay on the street dying. Years later, he strikes a deal to save this savior-turned sister and enters the virtual world. In a future Earth where advanced warfare has forced nations to settle issues virtually or else suffer the consequences, Ling Chen bursts into the scene and goes from unknown to legend. Yet all is not as it seems, for Ling Chen has a dark past, and there is a greater mystery at hand behind this virtual world.

To save his terminally ill little sister, Ling Chen enters the newly released virtual game world and joins a small gaming studio comprising entirely of women. From now on walking upon his path towards the pinnacle. An ancient, evil item almost forgotten by history, the “Lunar Scourge” helps forge his unsurpassable legend, and causes him to unknowingly step upon a path that is destined to be punished by the heavens, the way of the Shura.

- Description from Novelupdates

When a terminally ill young man awakens in the world of his favorite childhood game, he realizes he isn’t the protagonist, the destined hero, or even a major side character. Instead, he has become an extra—a disowned noble barely clinging to relevance in a world where strength determines everything. Worse, his fate in the game was to die an early, meaningless death.Armed with only his knowledge of the game’s storyline and a common system that tracks his stats and skills, he is determined to survive. But mere survival isn’t enough. He remembers a hidden easter egg from a long-forgotten anime collaboration: the Mangekyō Sharingan—a power limited by game mechanics but unrestricted in reality.With Kamui as his trump card, he walks the fine line between fate and freedom, seizing power from the shadows while avoiding suspicion. As the protagonist and his allies battle against demons and unravel the game’s grand destiny, he secretly builds his own strength—manipulating events, mastering forgotten arts, and even forging ties with villainous factions.Will he remain a footnote in history, or will he carve his own legend in a world that was never meant to be his?

I fell in love. Her name was Shirasaka Yukino. I could only look at her from a distance. However one day I heard that she already had a boyfriend. Even if I love her, I can’t have her. The devil sent me an invitation. I can make her mine!

Luo Yi, a high school dropout in his original world, was isekai’d into the world of the Witcher 3. Starting out as a weak boy named Roy in the village of Kaer, Lower Posada, he was determined to grow stronger, no matter what it took. The first step toward becoming a legend was to kill. And his first kill was… a rooster. ‘You gain 1 EXP.’ Of course, Roy had his own cheat system like all the other isekai protagonists. His first step to becoming a legend started now…