You are a really impressive performer. In T3, this is not so much a matter of skill or Charisma as the almost mystical ability to entrance an audience. This can be acting, playing an instrument, dancing or any performing art, but the rest of the text assumes it is the most common variant, singing.
When you sing, people stop to listen. They will not ignore obvious dangers, like a shoot-out, but become real easy to sneak by. When you sing about their melodramatic hook (such as a song about a lost brother or loved one), they cannot help but react, though the reaction will vary with the character. Any interaction going along with the mood of your song (such as Seduction with a love song) gets a +3 bonus.
Targets can shake the effects of your song with a Willpower roll against your Charisma , but must then react in some obvious way; walking away, ordering you to stop et al.