Ko gets an extra song Harris Jayaraj's peppy tunes in Ko are already rocking the charts! And now, the music director is all set to release a bonus song. 'Enjoy the bonus song 'Vetri padigal' in Ko releasing this Friday,' Harris tweeted. Meanwhile, Ko, starring Jiiva, Karthika, Ajmal Ameer and Piaa, is all set to grace theatres this Friday. Advance booking has already started! Rush and grab your tickets now!!! CLICK HERE FOR Ko preview.