[StayC enters ‘Billboard K-pop Hot 100 Chart’] Rookie K-pop act StayC has entered the Billboard K-pop Hot 100 Chart with their debut single “So Bad,” which ranked 90th on the chart issued on Nov. 28. The K-pop Hot 100 Chart ranks the 100 most popular Korean songs in Soth Korea based on their digital downloads, streaming figures, airplay and TV data. It was first published in 2011 by Billboard and Billboard Korea. In accordance with the uptrend, “So Bad” landed at No.21 on the Billboard World Digital Song Sales Chart for Nov. 25.  Written by Black Eyed Pilseung and Jeongoon, “So Bad” portrays the awkward yet straightforward sides of teenage girls when it comes to confessing love. StayC is the first girl group debuted under HIGH UP Entertainment, which was founded by the hitmaker duo Black Eyed Pilseung. Black Eyed Pilseung has written various hits such as “TT,” “Touch My Body,” “Cheer Up,” “Gotta Go” and “Dumhdurum.”