Answer:

endpaper

AnswerCrossword Clue
ENDPAPERPart of it forms the flyleaf
ENDPAPERBook decoration
ENDPAPERFlyleaf component or companion
ENDPAPERPart of a book
ENDPAPERChapter One preceder
ENDPAPERBook sheets
ENDPAPERBookbinder's sheet
ENDPAPERHeavy sheet inside a book's cover
ENDPAPERBook lead