Milf City frames its story around five women living in a modern city shaped by different cultures and everyday lives. Rather than following one shared character profile, it introduces residents with distinct occupations and personalities, including a bar owner, a woman from a traditional Japanese home, a supermarket owner, a casino regular, and an adventurous bungalow resident. That cast gives the game an episodic, character-focused premise.
Mahjong solitaire is the central stated activity: each woman has her own puzzle, and completing play offers rewards. The design links those puzzles to character galleries, each containing its own collection of pictures, so puzzle play and character-focused material sit side by side. Players can also skip an active mahjong game by pressing X, an option that makes the puzzle element optional in that moment rather than an unavoidable step.
The store lists Milf City as single-player, placing its character encounters and individual puzzles in a solo format rather than a shared multiplayer session.