In chapter 46 we get two near the end. The first is when Merry is told not to clean under Yumeji's bed, which leads to this conversation.
Merry: Though master said not to touch the area under you bed because it's a sacred territory. Is there something under there?
Yumeji: No there isn't!
John Doe: Oh, that's intriguing. This is a truth I must chase.
Yumeji: No you don't!
The second is when the three enter a day dream at the same time. Since John Doe is on Yumeji's head as a cat, Yumeji falls over moments after because he can't hold up John Doe's weight when he's a dream demon.