The person in this card's art seems to be the owner of "Outstanding Dog Marron", searching for him. In the OCG card, he appears to be calling out for Marron by the nickname "Wan-chan" (or "Doggy").
The Japanese name of this card is a pun on "Wan" (the Japanese onomatopoeia for a dog's bark) and "One" (the level of monsters affected by this card, including Outstanding Dog Marron). Both "Wan" and "One" written out in Japanese is "ワン wan". Whereas the English name is a pun on the phrase "Where Art Thou?"