Reenacting a Resurrection on the Spot for My Bro's 5T5

My brother is called 5t5, and I'm Gojo Aya. My brother, 5t5, has been cold and aloof since childhood. I do whatever he says. That's the Gojo family motto. I'm so obedient that I scare myself. I have a little quirk: in my dreams, I go back a thousand years. I wake up when I'm on the verge of death. My brother hates this, so I promised him I'd be careful and absolutely would not die. Then, when I was sixteen, I accidentally died. I thought I'd broken my promise. Twelve years later, I suddenly woke up again. I was alive. Turns out I'm an angel, and my mission is to maintain world peace. The sheer grandeur of this goal left me stunned. I promised my brother again, now a complete maniac, that I absolutely wouldn't die. My brother didn't believe me. I wanted to challenge the villain to a duel and show him what I could do, but my brother killed him. Just when I was at my wit's end, the villain set a trap and killed me. My brother went berserk on the spot, and I came back to life right there. This time, my brother was the one left stunned. Me: "I can do that ten more times. Want me to?" My brother's gaze grew increasingly crazed, but his smile stayed the same. "Shut up." * This is written in third person! Don't let my blurb fool you! The pairing is 5t5. 5t0 was adopted, and before the relationship changed, they were simply brother and sister. Theme: Be a kind person and stay true to your original intentions