There is a lot of stuff in here about "in the novel" that really should be marked as spoilers. Even if there are deviations in the manga vs the novel there are going to spoiled similarities as well. Don't include future info from outside sources without marking it as potential spoiler.
Im assuming his friend is also a "player" in this game world. I would be surprised if his friend was actually trying to stop the bad things from happening vs what i expect him to be doing (being the sole cause for all the characters to go crazy).