SEOUL — Japanese furniture retailer Nitori Holdings opened its first store in South Korea on Thursday and plans to expand to 200 sites in the country over the next 10 years.The first shop, housed in part of an E-Mart hypermarket in a residential area of Seoul, has a 2,500-square-meter sales floor. It offers furniture, daily necessities, bedding and other items similar to those available in Nitori’s Japanese stores, although many of these products are slightly more expensive in South Korea, partly due to trade tariffs.