I had seen an episode of Hell Girl once before and dropped it. But it had been a while and I forgot what actually happened in it. So, I rented the first DVD and my brother and I watched the first two episodes.
And now I remember why I dropped it before. While I guess it wouldn't be bad if you could ignore the formula and focus on the individual story, I just can't bring myself to ignore the formula. I hate shows that follow formulas or are "[whatever] of the week" kind of things.
And the individual stories themselves, at least the two I watched, both seemed predictable and pretty boring to me.
Clearly some people like this kind of thing, but it just doesn't work for me.