S//D is a traditional Yume Nikki Fangame. Unlike most Yume Nikki fangames, the Nexus can be accessed immediately by exiting the bedroom. Some NPCs give a fake effect which will trap the player in an enclosed area once it is used and certain chasers and events may cause the player to lose one or all of their effects. The lost effects need to be obtained again from where they're initially found if this happens.