The song "Really Mystified" by Elvis Costello and The Attractions is a heartfelt plea from the narrator to their loved one, warning them about the potential heartbreak they may experience if they choose to be with someone else. The narrator expresses their intense emotions and confusion, even going as far as crying over their fear of losing their loved one. The lyrics convey the narrator's deep love and constant need for their partner, as they ask for answers and patiently wait for their response. They feel mystified and puzzled by the possibility of their loved one leaving them, which leads to their emotional distress. The narrator believes that if their loved one chooses to go with someone else, it would be a great tragedy and a sin. They fear that their heart would be shattered and their world torn apart if their partner were to leave them. The narrator desperately longs for their partner's presence and fears the emptiness that would consume them if they were to be alone. Overall, the song portrays a sense of vulnerability and desperation, as the narrator implores their loved one to think twice before leaving. They believe that their partner's presence and love are essential in curing their loneliness and filling the void in their heart, mind, and soul. The song's emotional and heartfelt plea reflects the complex emotions and fears associated with the possibility of losing someone they deeply love.