Lee Sungjin showed off this relationship with top stars such as Kim Tahee and Kim Jungeun. In the latest recording of 'Happy Together Season 3 - Challenge Song' after 2 years NRG's Lee Sungjin has made a comeback into stardom. On the set that day, Lee Sungjin talked a lot about the 2 years he was away and expose some unbelievable connections. He said "I will disclose the relationships I have." Then pulled out a paper that had picture of him with Jang Donggun, Kim Jungeun, Kim Taehee, Kim Ahjoong and even singer Rain. Lee Sungjin revealed that "Before I debuted, in order to see pretty noonas, I attended acting school. The noona that I met there was Kim Jungeun Their relationship was so close that he would ditch acting class with Kim Jungeun sshi and hang out elsewhere." After Lee Sungjin say "I'm very close with Kim Taehee who debuted as the role of my girlfriend" "When I met her at the airport, I gave her a hug and the people surrounding us were so shocked." In addition to that, he revealed that Jang Donggun was his school's alumni and so he almost like his distant relative. This news surprised everybody there. Lee Sungjin's comeback to stardom and his amazing relationship stories will be revealed on 'Happy Together' tonight at 11:05. source: gomdoriii credit: Yahoo Korea News