Photo by Xavi Torrent/Getty Images for SHEIN There are many exploitative and harmful companies in fast fashion, but few move quite as fast as Shein. The Chinese retailer, launched in 2008, has rapidly gained popularity in the Western world over the last few years. It is unique for its suspiciously low price tags and chillingly rapid output, outpacing both Asos and FashionNova in the production of new items (creating roughly 60,000 fresh designs a month, compared with 20,000 and 4,000 respectively). Last year it became the world’s most popular fast fashion retailer by Google searches, overtaking Zara. This pace of…