People who are foxy are either sneaky or good looking. If you say someone is foxy, unless she has a long skinny nose and is stealing your eggs, you probably mean she’s hot.
If your dog is foxy, he might resemble a pointy-nosed fox, or he may be a wily beggar, convincing people with his sad eyes that he hasn't eaten for days. Foxy is also an informal term for an attractive person. This meaning comes from the Middle Ages, when a writer complained of women’s clothes that were so tight they had to stuff fox tails down the back of their skirts to hide their behinds. That is not weird at all.