The drug dealers in the warehouse do not seem like nice men. Y.T. makes the transaction, throws the vial up in the air, and Ng's mini-chopper snatches it up.
This does not make the drug dealers happy, and the appearance of Ng's Rat Things makes them even less happy. In fact, it makes them dismembered or dead.
When Y.T. hops back in the van, Ng is happy that they've managed to obtain the only sample of Snow Crash outside the hands of its makers and dealers.
Y.T. uses this opportunity to ask Ng about the Rat Things; as she's suspected, they're made from real dogs, pound rescues, which are enhanced with electronic parts. Y.T. thinks that's cruel, but Ng insists that the dogs are better off than they were.
In the past, Y.T. and Roadkill rescued a pit bull, named it Fido, and kept it until someone stole it; she wonders whether Fido is now a Rat Thing.
Perspective change: Guard Unit #B-782 comes awake, and listens to the other doggies barking about hurting bad men so that a nice girl could get away. #B-782 remembers that once there was a nice girl who loved him. He is happy to hear that she's safe. Implication: #B-782 is Fido.