This is a term coined to identify things like jiggling breasts, cleavage shots, panty shots, bra shots, closeup shots of women's breast, legs, butt, etc., and mild nudity all for the purposes of "servicing" the audience and having no relevance to the plot or characters of a series. The term has a second meaning covering things like massive action sequences, explosions, fights, etc., but it mostly refers to the first meaning.
Titles that are dismal or gloomy in nature qualify for the dark category.
