In Milk Girl - Sweet Memories of Summer, players engage in an open-world-like mission system where they can complete tasks in any order, focusing on building a relationship with the character Ayaka. The gameplay involves raising friendship levels by completing various missions, which can influence Ayaka's likability and lewdness.

The storyline revolves around the protagonist living with their childhood friend Ayaka during summer vacation, as they navigate her challenges related to her mother's milk production. The goal is to strengthen their bond by a specific date to achieve the true ending.

Milk Girl - Sweet Memories of Summer stands out with its fully voiced and animated drama segments, providing an immersive experience. The game also features easy controls, allowing players to interact with the environment and characters using simple mouse movements.