Of course this song had a story line!! it is a follow up to shout out to my ex!!! After you diss your ex and show him/her that you are so much better without them!!! the song comes as a sign that you completely moved on and ready for a new chapter in ur life!!
definitely listen to the album version of "no more sad songs" without mgk. it has jesy on the bridge instead and it's got more of the deep, storytelling vibe you're looking for :)
Me reacting as a RU-vidr (filming): Normal reaction, normal compliments Me not filming: "YES GIRL WORK IT" & screaming at the screen cause its just too good😂