While playing pause the game, goto options screen and select enter code.
enter the code
The Hollow Lord
(whether or not you need caps, unsure i put the caps in for it)
This will allow you to get the scythe from Vulgrim.
Once you have completed his collect 500 souls quest and have the Earthcaller, you can now purchase items from Vulgrim.
Press B to shop from Vulgrim.
Press RB twice and you will be able to pick up the scythe for 0 souls.