Kim Dong-hyun, the seventh-ranked fighter in the UFC world rankings, Ray Yang, the main character of 2015 Muscle Mania, are on Rainbow Live! Fighter Kim Dong-hyun reveals the secret of UFC victory. Turtle doll and red panties?! Unlike his tough tough looks, he's a delicate housekeeper and shows off his unexpected sloppiness! Ray Yang has been living alone for 9 years! And is the first identical twin sister on the show. Kim Dong-hyun and Ray's real single life will unfold!