After Hitomi fails to cure Riva and Riva runs away to the peripheries, Hitomi loses access to the company surveillance and data analysis systems. She buys illegal access to the cameras in Riva's house and some facial recognition, but doesn't have enough money to pay for the full suite of tools. She struggles to keep track of Riva.
Over the last two days, I’ve tried all of the facial-recognition applications I could afford. None of them delivered results. Then I started clicking my way manually through public security cameras. Riva isn’t on any of the streets in her district. She’s not in the corridors, elevators, or waiting areas at PsySolutions. Not in the cafes, clubs, bars, or museums that she visited in the past.
I look for clues in the archive feed from the apartment cameras. Riva left the apartment at 3:13 a.m. She was wearing an inconspicuous outfit, no bag. She looked perfectly normal, as if she were just going around the block to get some fresh air because she couldn’t sleep. But she never comes back. From the security camera at the corner of her block, you can see her walking away in the dark. After that, she never reappears.
von Lucadou, Julia. The High-Rise Diver . World Editions. Kindle Edition. Chapter 35.