This Lord Is Frail but Overpowered

[Highlight Warning: The Wind Pillar plot in Chapters 8 and 9 is OOC. Please be aware before reading. The comments are closed, so let's not fight, everyone. Orz] Blurb: The master of the Demon Slayer Corps has been replaced. The young man of unknown origin is named Hoshino Shugo. With black hair, snow-white skin, and strikingly beautiful features, he speaks gently and softly. He looks frail and often coughs up blood without stopping. His left cheek says, "Beauty beyond compare." His right cheek says, "Not long for this world." No one was willing to accept that someone like him was the new master. "To be honest," Hoshino Shugo began at the succession ceremony. Before he could finish, he turned aside and coughed so violently he could barely breathe, then gave a delicate smile. "I'm not very good at fighting and killing..." When the demons heard that the Demon Slayer Corps had a new master, they naturally came to see the commotion and took the chance to attack him while he was alone. As the demons surrounded him, the sword-wielding Tsukumogami at his side skillfully handed a sword to their master, an onmyoji. The sickly beauty instantly turned into a berserk warrior. His blade flashed, leaving no one standing and a field full of wails. The Demon Slayers, who arrived late, stared blankly at the demons strewn across the ground, their jaws dropping. This wasn't how it was supposed to go! "That's what I mean. I'm not very good at fighting and killing. Once I start, it's over. Boring." The Demon Slayer Corps: "...You're the boss, so you're right!" This story will be entering VIP serialization on Monday, January 6. Three chapters will be posted that day. Please support the story! (Bows) A few things to know before reading: 1. A feel-good power fantasy. Don't ask. The protagonist is simply the best in the world. 2. The CP is an original character who is at the very top of the power scale, the Child of God and Sun Breathing user. 3. I love fanon and major changes to canon. Please don't insist on scrutinizing every detail. 4. Character interpretations will inevitably differ, and there will definitely be OOC moments. 5. Please forgive me for not accepting writing advice. Thank you very much. Theme: Strive for self-improvement, persevere through adversity, and save the world