Logging in as a Monster

Briefly about Logging in as a Monster manga: 

The Abyss, the most popular PVP player virtual reality game, has never seen Jinhyeok lose. Jinhyeok gets an unexpected offer from his brother Jinho, a game creator, in response to the news that “Abyss World,” a follow-up to “The Abyss,” has been released.

Read Logging in as a Monster Manga.

The user is instructed to “Log in as a monster.”
“…What in the name of hell are you on about?

He might participate in a competition as the “Black Knight,” the recognizable figure from “The Abyss,” to mark the opening of “Abyss World.”

The question is, “What would you do for me if I did this for you?”