The Paparazzi is busy chasing after the singer's shadow.
I would suggest altering this becuase it reads in the progressive tense
It sounds as if you are literally writing the sentence as the events unfold
I would modify it to read as:
The paparazzi were busy as they chased after the singer's shadow
The paparazzi were busy, on the tail of the singer's shadow
Hope this helps
Student or Learner