It's hard to tell what's more evil here: the prank itself, the fact that the boyfriend spent weeks preparing it while his girlfriend slept, or the fact that he then put it all online.
James Williams decided that his girlfriend's fear of the evil ghost from The Ring was ripe for the pranking, and went so far as to making a fully working 3D puppet of a terrifying ghost with which to scare his girlfriend shitless. Did it work? In a word, yes. Be warned, as predicted, this video gets LOUD.