Demon Slayer: I Used Blood Demon Art to Slay Muzan

The System suddenly awakens, and the main quest turns out to be making me use Blood Demon Art to slay Muzan?

When Wang Shuo opens his eyes, he has fallen into the hell that is Mount Natagumo in Demon Slayer. He's become a member of the Demon Slayer Corps, but after being infected by the spider venom of Rui, Lower Rank Five, he turns into a half-human, half-demon “Spider Demon.”

With the System awakened, he wears a demon's skin while keeping his human reason. He must fight the bloodlust surging within him while searching for a way to survive amid the slaughter between the Demon Slayer Corps and the Twelve Kizuki.