Yes-No pillows are matching pillows. One pillow is blue, and the other is pink. "Yes" and "No" are each written on the sides of the pillows.
These were presented as a prize to the couple who appeared in the talk show, "新婚さんいらっしゃい! (Shinkon-san, Irasshai! - Welcome, newlyweds!)". The program presenter never told how to use it, though it is probably used for the declaration of sexual intention.