Here is the passage again:
Richie loves to walk his friends' dogs at Lake Eola Park.
For example, Kim's Labrador retriever Murphy or Gary's
bulldog Kembo. Beautiful women, Richie has learned, gravitate toward
guys with cute dogs.
The second part is an afterthought fragment. Good details support the first sentence, but those details do not include a main clause, the essential component of a complete sentence.