Mai-Yin was a young girl who lived in a village in Hong Kong and when she saw Shang-Chi fishing she asked her father to welcome him, but the father slapped her saying that no foreigner was welcome in the village. Later Mai tried to make friends with Shang-Chi but once again the father intervened who threatened Shang-Chi with a knife and who immediately punished Mai. When Shang-Chi found Mai left out of the house as a punishment, he welcomed her on his boat and taught him Zen fishing and Mai told him her story and why his father behaved that way.
Awakening on the Shang-Chi boat, Mai found a note telling her to follow the Zen philosophy but not being able to find consolation she decided to try to help her father by going to the base of Wild Tiger Mob and she arrived just as Shang-Chi was fighting against the Mob leader distracting him and ending up defeated and apparently dead.
Shortly thereafter Mai discovered that Shang-Chi was not dead and still resolute to help his father out of the underworld and drug addict followed him in secret and was actually really helpful in eventually managing her purpose.