"Restaurant to Another World" is a fantasy manga series that revolves around a mysterious restaurant known as "Western Restaurant Nekoya," which serves as a bridge between two worlds. The restaurant operates in modern-day Japan but opens its doors to customers from a parallel fantasy world every Saturday, a day when it is closed to regular patrons. The establishment is run by a stoic and skilled chef referred to as "Master," who prepares a variety of dishes that captivate the diverse clientele from the other world.

The narrative is episodic, with each chapter focusing on different characters who visit the restaurant. These characters include humans, elves, dragons, demons, and other mythical beings, each with their own unique backgrounds and reasons for seeking out Nekoya. The dishes served, ranging from simple comfort foods like curry rice and hamburgers to elaborate desserts like parfaits, evoke strong emotional responses and often bring back cherished memories or provide solace to the patrons. The food becomes a medium through which cultural exchange and personal connections are formed.

Key recurring characters include Aletta, a demon girl who becomes a waitress at Nekoya after being saved by Master, and Kuro, a dragon who frequently visits in human form to enjoy the food. Other notable patrons include Heinrich, a knight who discovers the restaurant during a quest, and Sarah, an elf who becomes enamored with the desserts. The interactions between the characters and their reactions to the food highlight themes of curiosity, discovery, and the universal appeal of culinary experiences.

The manga emphasizes the joy and comfort that food can bring, transcending cultural and species boundaries. The restaurant serves as a neutral ground where individuals from vastly different worlds can come together, share meals, and momentarily escape their troubles. The story is driven by the relationships formed within the restaurant and the impact that the food has on the lives of its patrons, making it a heartwarming exploration of food, culture, and connection.