Et Cetera Vol 5

Et Cetera Vol 5 by Tow Nakazaki. An Action manga rated Teen, published in English by Tokyopop in 2004.

Mingchao, a spirited girl from China, arrives in the American Wild West dreaming of becoming a star. She carries the Eto Gun, a mysterious weapon that fires bullets charged with the powers of the Chinese zodiac, and soon gunslingers and outlaws are after it. A rollicking Western action comedy.