You will see many boards during trip in Japan. One of those boards where you stick your face in a hole to take a funny photo with your face on a character's body.
Most everyone in Japan is familiar with this type of board at sightseeing places. Usually the design and words on the board intend to the sightseeing place.We call this type of board Kaohame-kanban 顔ハメ看板 in Japanese.
When you find the board, it is a good idea to take a photo with the board for remembrance sake and humorous effect.