The person belongs to dark 

In search of light

Leaves the dark

Found a rock 

Keeps the rock 

Ask the rock

"Hey rock, Where I can find the light?"

Says the rock 

"The light that you're
  Looking For is in the dark"

Goes to dark 

Found a mirror

Keeps the mirror

Ask the mirror

"Hey mirror where i can find the light?"

Says the mirror

"The light that you're 
  Looking for You already have"

Unsatisfied with the answer 

The person that belongs to dark

Leaves the dark

In search of light.