Spike buys a comic book and finds it fun even though there's blood and gore. Twilight sees him reading it and doesn't approve of him reading it. The book is called 'The Darkness'. how will is not go wrong. Right?
I am a big Spike fan, so most of my fanfics will have Spike and/or CMC as the main hero's. If you have come here for some logic than this is the wrong place...maybe