In a medium bowl, whisk together pudding, milk, whipped topping, and peanut butter. Cover with plastic wrap and place in refrigerator while you prepare the Nutter Butters.
In a microwave-safe bowl, melt the white and black candy melts in the microwave in 30-second intervals. Remove from the microwave and stir until melted.
Dip the Nutter Butters one at a time in the candy melts. Shake off excess and use an offset spatula to smooth the front. (You want to make sure the front surface is smooth so you’ll be able to easily write ‘RIP”.)
To assemble the cups, scoop pudding into each cup about ¾ of the way full. Sprinkle skulls and bones candy on top of the pudding, then top the cups with crushed Oreos.
Place Nutter Butter on top, with RIP facing out. (I placed the Nutter Butter next to the rim of the cup as opposed to the middle of the cup.)