It's been seven months since SISTAR last promoted, but they're finally back with their new title song, "So Cool", which they performed for the first time on tonight's 'Music Bank'. As with their previous title songs, "So Cool" was produced by Brave Brothers. It's an energetic dance track that expresses a woman's frustration at her emotionally unavailable lover, and so she tells him off in the verses. Fans won't get to see the hot 'tail dance' in the choreography, as Starship Entertainment decided not to show it in public broadcasts to avoid a controversy. The girls still managed to bring a great performance without it though, so check out their comeback stage which also includes "Girls Do It".