How does Michael Chabon use imagery in The Mysteries of Pittsburgh?

Imagery:

There was a faint golden stubble on his cheek and a flush at the pink skin of his throat. His eyes were clear and pale, as though he had not been drinking I felt something. It flew around my chest like a black bat that has got into the house, terrified me for an alien moment, and then vanished.

"Dad." Now that he really had me going, hiccuping and sniffling, so people turned around from their tables to look at this distinguished father speaking calmly to his wild-haired son, now in tears; now that he had reduced me to my childhood role and demonstrated to me just how far I had fallen in his esteem, he relented, tenderly, speaking as thought I had just wrecked my bike or got beat up at school and he was softly applying the fragrant Band-Aid.