Demon Slayer: Butterfly Wings

I traveled to the Demon Slayer World and was bound to the "Bond Thread" system. At first glance, I saw the broken bloodline on Butterfly Ninja's body and the broken heart under the smiling mask. The system said: [Save her and you can gain invincible power. I refused. Because I know that she must die in the original work, and that is her most heroic ending. But I can choose to give her the warmth she has never had before on her way to death. I taught her pharmacology, accompanied her in research, and watched over her when she had nightmares. She said: "In the forest, I may not live long." I smiled: "Then laugh truly, cry truly, and love me truly every day of your life." Later, during the decisive battle in Infinite City, before she died, she turned back and smiled at me: "Wait until I come back. "I nodded, and then used the last chance given to me by the system. Will— Not to save her life, but to let our love transcend life and death. Eternal.