Dong Si Cheng (Korean: 동스청, English: Dong Si Cheng), born on October 28, 1997, is a Chinese male entertainer and singer. His stage name is Yunyun (Korean: 윈윈, English: WINWIN). Born and raised in Lucheng District, Wenzhou City, Zhejiang Province, he primarily develops his career in mainland China and South Korea as a member of the South Korean boy group NCT under SM Entertainment.
