Gong and Cannon Fodder had the wrong children. After Cannon Fodder died, Gong was recognized as his relative, while Shou was Cannon Fodder's fiancé. Because there was something wrong with Cannon Fodder, all the relatives and others knew the protagonist's situation but still remained indifferent. The family line was disgusting.
Gong favors Shou, because Shou is a non-human being who understands nothing and cannot respond to feelings. Gong first feels that he likes Shou, and prefers Shou to Wen