When I thought a bit more about Jegolego's idea, I realized that a similar event occurred in the early scenes of Da Capo 2. The character who was in hibernation was a literal robot girl. Which, in turn, reminds me of an event from Chrono Trigger...
Anyway, how could this idea work? Here's a few ways to spin it...
* The characters live in a world that is recovering after an enormous war or crisis. It's not unusual to see ruins and broken vehicles.
* Robot girls used to be commonplace. Then there was an event which caused people to realize there was a serious problem with their programming.
Nearly all of them were "retired." The robot girl at the beginning of this story barely escaped.
* Humans need to sleep and eat. Robot girls have charging stations, and can function for days or weeks without needing power. This could become a problem.
* Robot girls are designed to acknowledge one person at a time as their master. Did this girl have a previous master? If so, is the person still alive? (If you're familiar with Mahoromatic, this reminds me of a few plot points from that series...)
* The same people who made robot girls also made similar creatures in the forms of boys and pets. (This is acknowledged in Chobits, though they don't figure into the plot.) Is it possible for two robots to form a relationship?