Toaru Majutsu no Index - Volume 19, Epilogue: They Will Not Let It End a Tragedy. Brave_in_Hand.

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.

Ye Chu is a miserable supporting character from a novel (she transmigrated).

She’s the most famous socialite in Shanghai, but her existence was to emphasize the magnificence of the white lotus female lead.

In the previous life, Ye Chu died in an accident. After rebirth (still in the novel), she didn’t only want to get revenge, but also change her fate, allowing every side character to have the opportunity to shine. Ye Chu and Lu Huai are a fake couple in their previous lives but reunited in this life.

They probed each other at every turn and slowly got closer to each other. They two fell for each other and confronted their enemies together.

- Description from Novelupdates

Ryo Tanaka, a struggling college student, works tirelessly at multiple part-time jobs to make ends meet. In a bid to earn some extra cash, he volunteers for a paid drug research study, unaware that it will alter the course of his life forever.The experiment takes a disastrous turn, leaving Ryo bedridden with a high fever for several days. But when he finally awakens, he finds himself in a world plunged into chaos. A deadly virus has ravaged the city, turning its inhabitants into ravenous, flesh-eating zombies. Streets once bustling with life now lay desolate, the remnants of civilization crumbling under the weight of the apocalypse.

Xin Yan was betrayed in her past life, brutally killed by her boyfriend and her best friend.But she didn't expect to get reincarnated.“In this life, I will plot my revenge against those who have harmed I and my family,” Xin Yan vowed.“Darling, don't you need me to help,” a coquettish male lead asked.Xin Yan felt her scalp tingle as she gritted her teeth.“Fine,” it wasn't bad to have someone take revenge on her behalf, was it?Have questions?