I have a sister-in-law who is obsessed with Celtic Woman. Yes, obsessed, and she'll admit to it. She buys every c.d., every concert DVD, follows forums, hoardes details, travels nationwide for their shows. Obsessed.
I have a friend who's obsessed with vampires, a la Twilight. She admits it, too, and her obsession has spread to any number of the new vampiric television shows, and all the novels she can, um, sink her teeth into.
Obsession as defined by merriam-webster.com : a persistent disturbing preoccupation with an often unreasonable idea or feeling; compelling motivation.
It dawned on me moments ago that I should own up to my own obsession. You know, writing.