A man hears a loud, rhythmic thumping on his walk home...

He turns around to see what is causing the commotion, and the sound immediately stops. Seeing nothing but a large casket, and rather confused, he continues on his way home.
Though he is sure there is nothing causing the racket, he is convinced he is still hearing the noise. The man cleans his ears and continues on his way, but still hears the thumping.
Concerned, the man looks behind him and the sound subsides again. The man begins to search the dumpsters and look over the fences in the area. He calls out to see if anyone responds, only to notice the funerary box a few feet behind him.
Visibly perturbed, the man begins to pick up his pace, but the thumping matches the tempo of his feet upon the ground.
The man pulls out his phone and opens the camera to look behind him while he walks, to discover that the pine box is "hopping" along with him, only a few steps behind. The man turns around and the thumping stops and the pall is stationary. The man opens the lid, but sees nothing.
Frightened now, believing the crate to be a death omen, the man stumbles backwards and breaks into a run towards his house. The thumping becomes more rapid, and the man screams for help. Rounding the last corner and fumbling with his keys, the man makes it through the door of his house; locking it behind him and pulling out his phone to dial the authorities.
The sarcophagus breaks through the door as the man shakily dials the last number. In a panic, the man drops his phone and runs up the stairs, locking himself in the bathroom. The man hears a momentary pause in the thumping while he rifles through the cabinets, searching for anything to defend himself. The thumping grows ever closer, as the man realises there is nothing but a substantial metal tin of cough drops to defend him.
The man braces himself in the tub, as the box bursts through the door, swinging the lid open on its hinges as if to eat the man. He throws the tin into the pine curtain, and all of a sudden, with a sigh of relief;
The coffin stops.

TL;DR it's a long build up to a pun