This particular episode of Invincible Youth aired a few weeks back but it has only come to my attention now. On the show, the G7 girls went crazy during a phone call with Rain / Bi. Kim Tae Woo, former member of JYP Entertainment group g.o.d called up former JYP Entertainment member Rain and the phone call was overheard by all of the girls. At first Rain was oblivious to that fact but once he heard the girls squealing in the background, he realized that they were in on the call as well. All of the girls seem to be excited except for 4minute's Hyuna since she probably knew him during her Wonder Girls / JYP Entertainment days. Brown Eyed Girls Narsha was the one that was the most excited and in her excitement she blurted out "Hello Oppa!" (Oppa is what younger girls say to older guys). However, she was quickly corrected and reminded that he was her dongseng (younger person) as she's a year older than him. Check out the whole clip below and thanks to rrx110 for the tip.