This tram car presents the ad of Chinese noodle with chicken. Therefore, it called "Chicken-ramen-gou" within the meaning Chinese noodle with chicken.
Aside from this, 8201 has a nickname "Shirakawa-gou" named after the river in Kumamoto city.
This photo was taken at the Gofukumachi stop. You can see a Japanese kimono shop behind the tramcar.