Liliput

Liliput was a magazine that, according to rumours spread by Coal Hill School students, was kept in the "library" that was the Staff Common Room, after having been confiscated. When Susan Foreman entered the Common Room, she found this to be false. (PROSE: Time and Relative)

Behind the scenes
In the real world, the magazine is spelled Lilliput. It was known for publishing female nudes.