Dickinson. The Thirteen Nights of Halloween

The Thirteen Nights of Halloween is a children's book by Rebecca Dickinson, with art by the author, published in 1996. It is available at the Internet Archive.

Here is a YouTube read-along:

As you can guess from the title, this flips the Twelve Days of Christmas to the Nights of Halloween, with the ill-omened Thirteen for the countdown number. The author sets it up with a rhyming frametale about a goblin in love who wants Halloween night to last longer so that he can work up the courage to propose. The future Mrs. Goblin then tells what "my goblin gave to me" on those thirteen nights, ending with: 

On the thirteenth night of Halloween, my goblin gave to me:
   thirteen ghosts a-booing,
      twelve vampires nibbling,
         eleven black cats hissing,
            ten skeletons rattling,
               nine bats a-flying,
                  eight werewolves howling,
                     seven lizards creeping,
                        six spiders spinning,
                           five pounds of worms,
                              four cackling witches,
                                 three jack-o-lanterns,
                                    two hairy toads,
                                       and a spooky owl in a gnarled tree.

It's a fun book, and a great model for adapting the traditional Twelve Days to other holidays, plus the frametale introducing the story of the lovers is a wonderful addition to the countdown.