I was rewatching La La Land, it made me think,

I wanna read the main theme, i mean a Harmony fic where the theme just clicks in, i want a masterpiece, i wanna cry but tears of joy. I want happily ever after, i want sweet surprises, i want my long hours for solitary confinement, i want something strong. Hope you can give it to me.

Please i dont want some teenage live, or smut. I want something pure and affectionate, something sweet, i would prefer if the characters are in their twenties. Long fics please, atleast 50k words.