Demon Slayer RPG, but the Player Wants to Usurp the Demon King

System: [Welcome, player, to the game Demon Slayer RPG. Get ready for a thrilling journey of slaying demons and meeting many like-minded companions...] Player: Skip. Then he turned around and ran off with Upper Rank One. System: [???] Wait, you picked the wrong side! * His temporary swordsmanship instructor, who was also Upper Rank One, posted a daily quest: [Swing your sword thirty thousand times, read for five hours, and train with me for three hours.] Player: Dog Breathing The lousy boss posted a long-term quest: [You good-for-nothing! Go find the Blue Spider Lily! Go kill the Hashira! You can't do anything, and you still have the nerve to ask me for a reward? What's the point of you?!] Player: Dye some red spider lilies blue and turn them in. Fail, die and reload, dye and turn them in again. Fail, die and reload, repeat x999... Ah, finally got a reward out of him. His childhood friend posted a weekly quest: [Come fight me, Ryu!] Player: Wrapped himself in wisteria flowers and charged in, shouting at the top of his lungs! Attack! In the end. During a battle with the Demon Slayer Corps, just before sunrise, a certain leader of the Paradise Faith, who'd been saddled with babysitting, happily tossed the player out. System, at full volume: [You have been kicked out of the demon faction!] Player: ? He turned to look at the Flame Hashira, whose hair blazed like fire and who looked like a giant owl. The player thought it over seriously: I'm Upper Rank Zero. Help me take down the lousy boss, and I'll make you the Demon King. Flame Hashira: I don't really understand what you're saying, but I'm all for defeating the Demon King! * During the Taisho era, the leader of the Demon Slayer Corps noticed a new group of demon slayers. They used all kinds of weapons, claimed to come from a mysterious dojo, covered themselves from head to toe, and were willing to sacrifice themselves in battle against demons. They also had an unusually strong love of basking in the sun, as if their entire faith rested on slaying evil demons. However, the Demon Slayer Corps could never uncover the group's true identities. That is, until the final battle, when the showdown at the Infinity Castle began Countless demons opened their scarlet eyes, while every member of the Demon Slayer Corps stood ready for battle. Then, under everyone's wary gaze, some of the demons suddenly pulled black cloth from nowhere, covered themselves with it, and turned to attack their fellow demons. Demon Slayer Corps: ??? The attacked demons: Are you crazy?! The demons who suddenly switched sides: Boo-hoo, buddy, would you believe me if I said my body suddenly started moving on its own? Meanwhile, a certain player, who was secretly embedded in the demon faction and had quietly made a name for himself, went around inviting people: Reply 1 to join the Take a Swing at the Lousy Boss Squad. Flame Hashira: Hahaha, 1! Wind Hashira: 1 Water Hashira: 1 Upper Rank Three: 11111 Countless demons creeping around in the shadows, secretly putting on their secret identities: +10086 The Hashira: Hm??? Player: Totally normal. Half the demon faction are double agents now! The lousy boss, spying on them: ???!! Player: That's right! I'm staging a coup! [System Notice: Congratulations! Your guild (dojo) has grown to more than 3,000 members!] [Guild battle rules activated: Once the guild leader marks an enemy target, members may not attack teammates, may not attack green-name units in the same faction, and may not fight half-heartedly. The system will forcibly take control of any character that violates these rules.] [The system is currently controlling 1,200 characters.] Player: Hehehe, hehehehe. The Great Battle at the Infinity Castle (x) The Double Agents' Great Rebellion Headquarters (√) The Player's Ongoing Coup (√) #A Look Back at the Demons Who Became Double Agents, Willingly or Not# #Player: Overthrow the lousy boss! Help me become Upper Rank Zero! I can make demons stop eating meat and let them bask in the sun!# #Akaza, who wants to reach heaven and reunite with his wife as soon as possible: Anyone who won't become a double agent can die# #To get the happy ending, the game system struggles to produce bugs# 1. As described above, a goofy story starring a player who causes trouble without restraint. Theme: Appreciate the beauty of life.