A monster in a prison

I put my heart in prison
convicted for his short vision
Spending years in his cage
his frustration turn into a rage
Start acting strange
He's hitting his head into the walls
He screams and yells until he falls
But..someday... somehow
He started to smile
He stopped screaming for a while
He wiped the tears from his eyes
He felt happy every sunrise
Because he had a belief
That you owe the way of his relief
That you have the key
to uncoff him and make him FREE !!