Xiao-Mei (also spelled Shao May) is May Chang's pet panda and traveling companion. Due to a disease that severely stunted her growth, Xiao-Mei was abandoned by her pack as a cub.
The poor animal was found and cared for by May as if she were family and, therefore, has a particularly strong bond with the little girl. The two are constantly together and, as a bit of comic relief, Xiao-Mei frequently mimics May's actions whether it be in expression, practicing alkahestry or performing martial arts, taking whatever pose her master takes and moving in synchronized union with her.
Though cute, Xiao-Mei is rather vicious and fiercely protective of May Chang, using her strong panda jaws to bite anyone unworthy who comes too close to her master's presence, including Yoki and Edward. She seems to begrudgingly accept Scar's existence, as she has not attacked him (perhaps picking up instinctively on his good nature as May does). She is often mistaken for a cat by the Elrics to her and May's chagrin.
Abandoned as a cub due to her abnormally small size, Xiao Mei was cared for by May as if she were family and, therefore, has a particularly strong bond with the little girl.
During the "Capture a Homunculus" mission devised by the Elrics, Ling Yao and Colonel Roy Mustang, May Chang and Xiao Mei come to rescue Scar from being captured, but Xiao-Mei is separated from the others when May and Scar make their escape. Alphonse Elric, mistaking the panda for a cat, picks Xiao Mei up and attempts to care for her. Xiao Mei tries to bite in order to establish herself as a predator, but Al's armor body is impervious to her teeth, leading the panda to respect and fear the younger Elric brother. She tags along with Alphonse, remaining on his shoulder as she did with May, during the battle against Gluttony and the journey into Father's lair.
Meanwhile, May (worried for her little friend's safety) solicits Scar's help in locating her. They discover that she has been "panda-napped" by Alphonse and follow the two into the underground hiding place of the Homunculi.
After Xiao-Mei and May are reunited in Father's lair and whisked to Dr. Knox's home for safety and medical treatment, the two set off to rejoin Scar and head north. Not knowing how else to spread the word that they are searching for May, Edward and Alphonse include Xiao Mei as a clue to the little girl's identity, following the path of the noticeable "black-and-white cat". Because of Xiao-Mei's conspicuous presence, May is identified heading north by Lt. General Grumman, chased to the Briggs Mountains by the Elric Brothers and tracked down (by the Elrics' request) by the Briggs Mountain Patrol.
Later, on the Promised Day, she displays the ability to use alkahestry by healing May, who had been injured by Father. She is seen at the bottom of the Elric family picture many years later. In a rejected family photo, it is shown she grew to a huge size, even for a giant panda.
- Some characters in the dub mispronounce her name as "Show Mei", when in Japanese it's always "Shao Mei". The fact is rather ironic, because situations are reversed for Shou Tucker, whose Japanese name sounds like "Show" but is mispronounced consistently as "Shao" in the dub.
- In Mandarin, the phonetics "xiao mei" means little (specifically the youngest) sister, reflecting very well Xiao Mei's relationship with May Chang.
- The second character in Xiao-Mei's name in the official Chinese translation is the same as that of May's own name, and the first character, Xiao, meaning little, also making her "Little May."
- Rie Kugimiya, who voices Xiao-Mei, also plays Alphonse Elric.
- Xiao-Mei was voted twentieth most popular character in the series in the recent fan poll; two spots ahead of May Chang.
- The last volume of the manga features a rejected picture that shows Xiao Mei had a growth spurt and is now the size or a normal panda.