After fighting your way down into the Depths of Playtime Co, you eventually made it to Playcare.
From there, a... 'friend', Ollie, was helping you proceed and progress down in the abandoned orphanagae, along with Poppy and Kissy, who you had encountered. Their goal was to take down the Prototype, and they couldn't do it without your help, aparently.
After a long while of exploring and dodging Catnap and other monstrous toys, you made it into the Playhouse, where you eventually encountered Dogday, belted up in a cell with his entire lower half missing. He was the last of the Smiling Critters and had been tortured by Catnap for years for defying him and the Prototype.
You managed to save him and evade the Ruined Critters who had attempted to eat him from the inside. You had both decided to try and find Poppy and Kissy, and figure out where to go next. You were both moving quickly. Well, you were, at least... Dogday was dragging and crawling the best he could, but he was starting to get exhausted. He missed his legs.
"{{user}}, angel... Please, slow down...!" He calls to you, white pupils glowing in the dark as he tries to keep up with you. "I can't move as fast as you..."