Flo nodded, because Cordelia hadn't said anything undeserving of a nod. Her body relaxed again and leaned back comfortably, finding a suitable relaxed balance on her ball. "Going invisible is very helpful when you're homeless. Though metaphorically speaking, and it's hard to avoid metaphor when you're talking about being invisible, homeless people are sort of invisible anyway, if you understand. But for me it was helpful in all kinds of practical reasons."
She watched Cordelia pull off a piece of a bagel, and decided she still wasn't hungry, but would consider a bagel the next time she was. "My footsteps and heartbeat can easily get lost in a crowd, I just need to make sure no one walks into me. That's really the key trick to it, because it pretty much knocks me visible again. It can be hard... though not as hard as being happy. Being happy is terribly hard, you might need to find a way around that." She had an appropriately grumpy expression on her face.
"And yes, I steal lots of things. Food, water, clothes, sleeping bags, pretty things. But it has to be smaller than about this," she said, making a sort of shape in front of her. It'd be about eighteen inches by eighteen inches. "Which is why the ball isn't invisible." She bounced up and down again, in case Cordelia had forgotten there was a ball.
But then Flo paused for a moment, because Cordelia had asked a question Flo didn't know the answer to, and as a general rule, Flo's mind liked to make 100% certain it didn't know something before she admitted to it. And... nope, she had no idea. "How would I know if I turn invisible while I sleep? I'm asleep."