Craigslist

There was no need to include a "pet-friendly" mention in the description of a Chicago apartment for rent on Craigslist.

Instead, a four-legged pet with an eye for the camera turned the two-bedroom apartment's ad on the popular website into a veritable game of "Where's Waldo," or, in this case, "Where's Otis."

Otis is the Great Dane-German Shepherd mix belonging to John, 29, and Sara, 28, Kanive, the Chicago couple who posted their $1,900 per month rental in the city's Lakeview East neighborhood on Craigslist earlier this month. The ad, describing the apartment's "open layout" and "tall ceilings," was your standard, run-of-the-mill posting had it not been for Otis photobombing each shot.

"The first picture I took, of the living room, he was just laying on the floor," John Kanive told ABCNews.com. "So when I saw that picture, that's when I got the idea to place him in all the pictures."

Otis proved game for his owner's antics, obediently staying put in each of the strategic locations he was placed so he'd be just barely visible.

John Kanive said he executed the photo-bomb, "just because I thought it was funny," but it proved to have a more strategic advantage.

"It did create a lot of traffic to our ad," he said

Less than 24 hours after the ad was posted, the apartment the Kanives have called home for three years was rented.

"I would say pretty much everybody that replied to the ad had something to say about the dog in the pictures, mostly like, 'P.s., I love your dog,'" John Kanive said.