In 2019, approximately 2.5 billion people played digital games. With the popularity comes both concerns about possible negative consequences such as violence as well as the potential for positive outcomes such as improve social skills and prosocial behavior. This thesis proposes the real-game mesosystem to understand the important role of the physical environment which has rarely been examined in previous studies. We conducted a true experiment with 2x2 factorial design with two independent variables, Game Mode (collaborative v. competitive) and Game Setting (same room v. different rooms), using the game Overcooked 2. The dependent variables are Friendship, Social Closeness, and Prosocial Behavior. We found main effect of Game Setting on Friendship, and Game Setting by Game Mode interaction effects on Social Closeness and Prosocial Behavior, all effects are medium-small. Future game studies and designs should be more aware of the physical environments where the games were, or will be played.