详细介绍：Na Du-su (Lee Seung-hyeon), who sports the nicknam…Na Du-su (Lee Seung-hyeon), who sports the nickname of "Yalkae" (meaning "cheeky, cocky person"), has been a high school sophomore for two years. His partner-in-mischief Yong-ho (Jin Woo-young), whose father runs a hospital, is also re详情