DKJ’s Xero poster is an endorsement cardboard poster product that Dok Go Jin endorses.
Gu Ae Jung was venting out on the poster as to why in Dok Go Jin’s broken situation he still continues to bother her. While poking the poster, she accidentally places a mark on it. Fearing Dok Go Jin will scold her, she starts to rub it off and blowing on it. But when Dok Go Jin arrives, he only sees what he thinks is her admiring it (him).
She also uses the cardboard to practice a dialogue she intended to say to Dok Go Jin of her intentions to have a good life with Yoon Pil Joo and not to shake her resolve anymore. Hearing her dialogue, Dok Go Jin asks her to come over to his house to see something. Instead of always doing what he commands, she insists that he wait for her if he’s interested in going on a picnic with her.