This is the
most important part of this song. Louis' sass always completes a One Direction Song. Just imagine a song without Louis' sass for a moment. What do you feel about it? It feels incomplete. Without Louis, there's no One Direction, same as if the others weren't there too, there would also be no One Direction. Every member is important. Every member has their own distinct personality traits. Louis is the sassy one, therefore, without it, it's a broken song.