Demon Slayer: Hand in Hand, Together Until Our Hair Turns Gray

What if Tanjiro successfully became a demon in the finale? What if demons conquered Japan? What if foreign forces joined the war as well? What if characters from other anime worlds came to this world? An infinite multiverse, infinite possibilities! This is a story about family, friendship, love, and regret. Opening: Fireworks flicker in the moonlight, just at the edge of my and Grandpa's vision. Sitting quietly on our stools, we reminisce about the past. Ending: Night has fallen. A few more wrinkles show on Grandpa's peaceful face in the moonlight. “He said the firecrackers were too loud, so from now on I should bring flowers when I visit.” “We're friends, right?” “We're friends. Good friends. You're my support, my pillar of strength, the one who helps me through my bad moods, stands by my side, listens to me, and has my back. Having you here is worth more than a thousand casual acquaintances.” “If you come walking toward me with a smile, on the first clear night after fresh snow, beneath a full moon, with pale shadows spread below and silver light flowing above, then between the moonlight and the snow, you will be the third incomparable beauty.” Opening: “I never have to grow up. Grandpa will protect me like a tree.” Ending: “At that moment, the tree fell, and I grew up.” Some character traits have been changed for this story. If that bothers you, please don't read. (The timeline has been changed slightly.)