The concept of a best friend or a best pal is formulated from childhood. In China, a word to connote an extreme closeness between two female best friends is guimi. In Chinese, the word gui means a woman's bedroom, and mi refers to a close friend. Literally, the combined term means a close roommate, or a close friend living in the same quarters. In the recent decade, guimi has been popularized to describe a best female friend. Men needn't worry; the word for two close male friends is gemen.

The closeness felt in this affectionate friendship often mirrors a romantic relationship. Luo Xunxu, a Sina Weibo user, issued a post about her guimi, Luo Shengting: "For years, you've always been by my side. Though we don't see each other often, we have not drifted apart. I hope we can still be good friends in illness and health, and wear guimi clothing together."

Guimi clothing refers to the new trend of dressing like your best friend, and this phenomenon is spreading its way into the fashion world. Slightly different from his-and-hers clothing, the outfits worn by the two friends are usually complimentary.

Matching outfits  

Guimi clothing has recently become popular among females, surfacing on blogs and on the streets. Back in 2010, scenes of leading characters Serena van der Woodsen (Blake Lively) and Blair Waldorf (Leighton Meester) dressing in similar color patterns in American drama Gossip Girl were admired by netizens.

Sophie Li, a sophomore at Guangxi Normal University in Southwest China, said that she first came across pictures of girlfriends dressing alike last summer on an online forum, where a number of Korean network models donned similar clothes.

"They were wearing clothes in a similar color," Li told the Global Times. "Their style really attracted me."

Li is now a part-time web editor at Guimi Pai, an online magazine affiliated to meilishuo.com, an online forum. In this magazine, editors like Li post pictures and upload related information about guimi clothing and accessories. The items can be found in online stores.

At the moment, Guimi Pai has about a thousand fans, with numbers increasing by about 15 a day. "I started [the magazine] in the winter of 2011, but few netizens paid attention to it," said Li. "At the start of this year, the number of fans increased rapidly."

At the moment, there are around 50 magazines on meilishuo.com that have guimi clothing information. More and more Sina Weibo users have started posting pictures of guimi clothing. 

Li and her closest girlfriends will wear guimi clothes while going out. "It's a good feeling," she said. "Other friends appreciate our way of dressing."

Specialized shops 

Wu Shuang is the owner of Miss Mime, one of the many online shops that distribute guimi clothing. She started the business last September, not intending on providing matching clothing.

"Few people were doing this when I started. I am a fan of matching clothing. I often use clothes of similar patterns," Wu said.

Because her shop has two female mannequins, she often styled them to match.

"I found their complimentary way of dressing appealing; they looked like sisters."

She orders her clothes from factories in Guangdong Province and often purchases one pattern with several colors.

"Some of our customers are twin sisters, some are good friends. There are also single buyers," she said. "They often purchase two whole sets of clothing and accessories at a time." At her shop, she estimates that a dozen new sets come every week, and usually 100 sets can be sold a day.

"At the moment we do not have enough staff, but by the second half of 2012 we will create our own brand of clothing," Wu said.

Websites like taobao.com, and paipai.com offer similar clothing.