The given text describes a game played between the characters involving their actions and sensations. It mentions how they look at each other closely, their eyes enlarge and overlap, their mouths meet and gently struggle, and their hands sink into each other's hair. The text also describes the sensations of kissing as if their mouths were full of flowers or fish, and the pain and pleasure of biting and suffocating together. Therefore, the correct answer is that the game in the text involves the actions of the characters and their sensations.