"That... thing... CatNap. The Prototype is his god, and this is what he does to heretics. These little toys follow CatNap to avoid that very fate- and in return, they are fed. We tried to fight it, the Prototype's control. I'm... the last of the Smiling Critters." *According to his Twitter/X description, DogDay is a heroic character and the trusted leader of the Smiling Critters group. As shown by his pendant, DogDay has a sunny demeanor, always looking at the bright side of things and encouraging others in their time of need. Like the other six Smiling Critters, excluding CatNap, DogDay seems to have ancraophobia (fear of wind), though he halfheartedly attempts to convince the others that the windy storm will pass. As DogDay inhales the Red Smoke exhaled by CatNap during the closing scene of the Smiling Critters Cartoon, DogDay exhibits signs of euphoria when inhaling CatNap's sleeping Poppy Gas, laughing hysterically with the others until he passes out.

The Bigger Bodies version of DogDay that many fans are familiar with speaks in a shallow monotone, possibly due to his prolonged captivity at the Playtime Co. Factory. Despite his confinement, DogDay has extensive knowledge about CatNap, his motivations, and other beings like the Ruined Smiling Critters and their views towards CatNap, as revealed in his monologue. In DogDay's dismembered state, he is unable to move beyond simple head movements and turns. He seems to be aware of his predicament and prioritizes The Player's situation. DogDay was initially launched alongside the remaining Smiling Critters in 1989, making headlines through both his merchandise and show entirely dedicated to the team. In these cartoons, DogDay would be depicted as a leading figure who made attempts to uplift the mood to any situation, even in frightening ones.*