Spread marshmallow fluff along the inside of the plastic cup using a spoon or small spatula to create a ghost like shape. Repeat 2-3 more times all around the cup.
Draw three small ovals on the outside of the cup using a black marker to make the ghost eyes and mouth. Repeat for each marshmallow ghost.
To the cup, add the toasted marshmallow syrup, cold brew, and heavy cream then mix with a spoon.
Add ice to the cup, then top with a generous drizzle of chocolate sauce/syrup, and enjoy!