Part of a novel

He was back in the world of green. No one would look for him here. He was floating on a gentle zephyr that swirled around and within him, sheltering his troubled mind. It formed a thin film on his being, like a caccooned caterpillar before his metamorphosis. Nadir would often venture out into the park two streets behind the hospital. So far no one had found about any of his horticultural escapades. It was his very own macrocosmic heaven. Standing on top on the deep cavity in the earth where rocks tumbled down into the well, he would pretend he was at the Grand Canyon. The tiny boulders would appear to be giant plateaus; the dirty pond was his secret, filth-ridden swamp. He would gingerly wade through the pond, trying not to provoke the crocodiles that lay dormant several feet below. Such was his imagination.
Of all picturesque adventures nature had to offer, he liked his make-believe Amazon forest the best. Darkly green. Greenly dark. His megalomania had become his psychological sanctuary. He had been here before. He knew this place, it was his comfort zone. An array of trees huddled together hiding thousands of well-protected secrets. Secrets his sister had shared with him many years ago. He called out to Nadya. Was she listening to him like she said she would? Did she know how they would test him next? Nadir knew she liked this park. She would hide behind the trees and stand motionless, pretending to hide from Nadir. He was too small to understand her teasing. He would start whimpering till she came out from the tree trunk and picked him up.
They had come here often on hot summer days. And here he was again on a hot summer day. Looking for her. Thanks to Karachi's humidity, not a leaf dared to stir. The forest lay still, quiet and unperturbed. Last rays of sunshine pierced through the hollow gaps between branches, forcing their way down below where Nadir stood awe-struck. He felt wholly insignificant. A microscopic dot facing a wild, beastly world. The fissures and cracks in the ground suddenly seemed to open wider and wider still. The earth would engulf him now. With a snap of a branch, he ran.