I think that this is about Dan Reynolds and his wife, Aja. They are in a band called Egyptian together, which could be part of the line "Cleopatra is the only one you love". I don't think it is directly about the Greek Myth, because Dan usually tries to right things that are meaningful to him, and I think the whole "Cleopatra and Caesar" things are metaphors about his fame and love life.
I think that this is about Dan Reynolds and his wife, Aja. They are in a band called Egyptian together, which could be part of the line "Cleopatra is the only one you love". I don't think it is directly about the Greek Myth, because Dan usually tries to right things that are meaningful to him, and I think the whole "Cleopatra and Caesar" things are metaphors about his fame and love life.