While he was following the directions from Igneous, Yi Chen was in the workshop trying to assist the old man to fix the music box of one of the nobles who had dropped by the family shop.
The old man could barely see properly thus Yi Chen's eyes were helpful.
Seeing the young man seriously taking apart the music box the old man couldn't help but admire him. He finally understood why his daughter was infatuated with this person. He not only saved their lives but he had excellent mechanic skills and he was very knowledgeable despite not recalling anything except that he had a wife.
The only reason they knew his name was because of the embroidered name on his t-shirt. They simply called him Chen but they didn't know his origins.
Old Du would truly feel at ease if he left his daughter in this man's hands but the man didn't like his daughter and he kept emphasising that he was married.