Percy is the evil old Victorian doll owned by Pops as a child and the main villain of Pops' story of Regular Show Halloween Special, Terror Tales of the Park. He had the ability to talk and spoke with a deep voice, which is very strange, considering that his appearance is that of a cherubic, really young British boy. He was the most sophisticated doll of his day, with 250 phrases stored inside. Yet the only real phrases we heard him say had to do with an obsessive desire to draw on peoples' faces. He drew on Pops' face after Pops tried to throw him away, and when Pops tried playing teatime with him after Mordecai and Rigby threw him away, Percy became aggressive and wanted to draw on Pops' face more. Mordecai and Rigby tried to rescue Pops, but Percy escaped and went into the basement.

When Mordecai, Rigby, and Pops went after him, Percy knocked Mordecai and Rigby unconscious with a shovel. Percy demanded Pops to bring him a marker so he could draw on Mordecai and Rigby's faces but then Pops stood up for himself and told Percy that it's not cool for a grown man like him to play with dolls and that Percy must go away. Percy then ran towards Pops to attack him while Pops did the same. Pops kicked him into the furnace where he perished.