Brody wrote "Lightning Bug" by himself, and it was inspired by one of his first songwriting trips to Nashville, Tennessee. He remarked that he wanted to write a song "that captured the magic of being caught up in a warm summer night. It’s meant to tell the story of being in love with that special someone, with an almost dreamlike soundscape".
Critical reception
Nanci Dagg of Canadian Beats Media referred to the track as a "heartfelt love song", adding that it "takes listeners to that place where those magical memories of falling in love happen while providing everyone that listens to it a bright spot in what has been a challenging year for us all". Courtney Fielder of Country100.7 called the song a "hit", saying it was released "just in time for summer".