He as the equation is changed

Like what he said at the start, chemical equations can be good, or totally different once changed.

He was forced to do the meth stuff because of his miserable situation at the beginning. Yet later on the other hand, the man, who used to be tolerating and swallow every humiliation from life, now started to enjoy a kind of joy after getting the chance to break the law. To him it was also breaking the circle that had been confining him. From suffering to enjoying, now he as the equation is changed.