Friday the 13th Part 2 is 1988 novelization of the film of the same name written by Simon Hawke and published by Signet.
Official Summary Edit
Vickie didn't want to disturb Jeff and Sandra. She had heard the vigorous sounds coming from their bedroom, and knew they must be lying exhausted in each other's arms by now.
But she had to see them. She had to warn them what was happening here at Crystal Lake, as thunder crashed and lightning flashed.
Timidly she opened the bedroom door and looked inside. The sheets were pulled over two figures lying on the bed.
"Sandra," Vickie whispered.
Then the sheet was thrown back, and a hooded figure sat up...
... and Vickie screamed and screamed and screamed...