Catherine is an erotic horror platformer set in modern-day Japan. In the single-player campaign, players take the role of Vincent Brooks, who begins experiencing nightmares after meeting a mysterious woman named Catherine. These Nightmare segments require players to climb up movable, collapsing blocks, while the Daytime segments focus on dialogue with other characters and managing Vincent's relationships. Two-player multiplayer modes include Babel Mode, which focuses on four large Nightmare stages, and Vs Colosseum, where players compete to reach the top of the stage first. Catherine features a non-linear morality system, where players' minor choices determine Vincent's character and change the game ending.