The tapes are items scattered around certain areas of Yandere Simulator to be found by the player. The tapes elaborate on the lore of the game, mostly pertaining to information that would not be available outside the tapes.
There are currently three known sets of tapes: Mysterious, Basement, and Headmaster's.
An investigative journalist tells his backstory about what happened when he tried to be a hero and stop a yandere girl. These tapes can be proven wrong if the player decides to use non-canon elimination methods in 1980s Mode.
The yandere girl of 1989 from the Mysterious Tapes interacts with her senpai. The interactions range from kidnapping the young man to dragging him all the to America.