Defining friendship As Chung-jen describes it, although the two are twins, they each have their own individual troubles. Because of pressures caused by the structure of his body, Chung-jen suffers from very painful kidney stones. It has proven impossible to break them up with ultrasound shock waves, to extract them with endoscopic surgery, or to fully ease the pain with analgesics.
就像忠仁形容的，雖是孿生兄弟，兩人卻各有專屬的病痛：由於身體結構上的擠壓扭曲，忠仁苦於超音波震不碎、內視鏡手術取不出，甚至止痛藥也鎮伏不了的腎結石疼痛。