Oldest Child is a cooperative storytelling card game about a vampire. There are no winners or losers. In this game, you will be playing as yourself. Although you might change throughout the game, you are always you. If you need to change certain aspects of your own life to make the narrative work better, you are free to do so. The important part is that you be yourself and make choices that only you would make.

In Oldest Child, you and a group of friends take care of a vampire for three years (the game taking only 4-6 hours). Her kind is suffering from a mysterious illness that cakes their noses with a white fungus, suffocating them, sometimes leading to death. It is named The Sufoca (Romanian for Suffocate). Lyda, the vampire you are taking care of, is sick with the illness and in a state of relative weakness.