Swingin' Party Lyrics

Lyric discussion by misanthobi 

Cover art for Swingin' Party lyrics by Lorde

Dear native speakers,

does anyone know why you should bring a lampshade?

Btw, after I heard this song for the first time I thought she was singing about a collective suicide plot - "here it`s never ending, can´t remember where it started" - the eternity you find in death; "swinging party", "we hang side by side" sounds still very romantic to me, but I guess I was wrong