Themistocles Nicholas "Themi" Leftheris (born December 20, 1982) is an American-South Korean pair skater. With partner Naomi Nari Nam, he is the 2006 Skate America bronze medalist and 2007 U.S. national bronze medalist. With partner Ji Min-ji, he is a two-time (2016, 2017) South Korean national champion.