It's wrong to lie about your pet.
Lisa is talking to a new guy whom she likes, whom happens to be very passionate about animals.
Lisa wants to impress the guy.
Lisa tells the guy that she is considering adopting a dog and asks for advice.
Lisa tells the guy that she has a dog when in fact she doesn't.
The guy gives her advice, and they go on a date to the animal shelter and have an amazing time.
The guy comes over one night and finds out she was lying and leaves, ending their friendship.