The novel opens with Hiroshi's greeting to his wife, Ata chan, who has just returned from a trip to the seashore. Hiroshi tells Ata that he is very happy to see her, as she is the only one who has forgotten about his birthday. He tells her that it is his birthday, and he invites her to his house for a party. At the party, Hiroshi tries to play a game with Ata, but the game is not a good one.