Kyoukai Senjou no Horizon - Volume 8C, Chapter 58: Curious People in a Curious Place

The first time they met they had battled fiercely, just for a mere bunch of herbs. She needed it to save people, and he wanted to use it to save his own life.

Adam, who mysteriously transmigrated to the Marvel universe over a decade ago, has established the powerful Umbrella Corporation. Now, he's unleashing a new era of viral evolution. The Progenitor Virus, T-Virus, C-Virus, and G-Virus are just the beginning of his sinister plans.As heroes and villains struggle to contain the chaos, new threats emerge: the Blacklight Virus, Z-Virus, and the dreaded Cthulhu Virus. Adam's shadowy influence grows, pushing the Marvel universe to its limits.

Summary Version 1:

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.

Summary Version 2:

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.