How does Janet Evanovich use imagery in Hot Six?

Imagery:

"After this guy ran over the victim, who just happened to be his ex-wife, he beat her with a tire iron, raped her, and tried to set her on fire. He was charged with vehicular manslaughter because according to the M.E. she was already dead when he took the tire iron to her. He had her soaked in gasoline and was trying to get his Bic to work when a blue-and-white happened to drive by.'
Little black dots danced in front of my eyes. I sat down hard on the fake-leather couch and put my head between my legs."

"I sat there for a while, watching nothing happen. No action in Hannibal's house. No action in either of his neighbors' houses. Very boring. No one on the bike path. No dog walkers. No joggers. Too dark. this is why I love surveillance. Nothing ever happens. Then you have to go to the bathroom and you miss a double homicide."