That seems to be the major problem with NotDead fics; bringing people back to have sex. Which I'm sure the dead people wouldn't mind, but it's not really very logical. There'd be a lot of dead people roaming the world if they could do that just because they wanted to get it on.
From a post on fanficrants. Note: The post itself is under cut tags for spoilers for Harry Potter, Trigun and Cowboy Bebop character deaths.