Harmony. Zarry

Zayn met Harry in a gay strip club...there was the beginning of Harry Styles the super star..tabloids know Harry as the Solo artist that sings with passion..but flees from writing his own songs. Zayn knows Harry as the 24 year old that married, and knocked up his sister after years of being his ghost writer Zayn never liked the thought of Harry marrying his sister... Zayn's kids and wife know Harry as uncle Haz, and are happy every time they get an expensive gift from him every Christmas and Harry well Harry knows himself as the man who's in love with his wife's brother.

Or The one where Zayn writes music for Harry styles his famous brother in law and soon enough something inappropriate blossoms from their work and family based relationship.