From the Super Mario Wiki
Super Mario 64 / Super Mario 64 DS
Bookends only appear in the course Big Boo's Haunt. Bookends possess sharp teeth and disguise themselves as regular books within a bookshelf. They hop out to attack Mario if he gets close enough. The green books disappear if they hit anything, including Mario. There is 1 room that contains a different type of Bookend. The other type flies quickly from 1 shelf to the other trying to attack Mario. In the DS version both types of Bookends do the same thing to Luigi and Wario.
Mario Party 8
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