Actress Hong Soo Ah has been busily supporting the debut of her labelmates CHI CHI in various event performances the past couple of month. She's finally joined them on stage for today's episode of "Show! Music Core" for a surprise performance of their title track, "Don't Play Around"! A representative from their agency, Yedang Entertainment revealed to Star News, "Departing from the fact that they're labelmates, Hong Soo Ah and CHI CHI are more like close sisters. In an effort to lend the girls a bit of strength, she's been joining them in their promotions despite her busy schedule. She's put in a lot of sweat for this, so please look forward to it!" Check it out below! Source: Star News via Nate