Surprise! A manga series I don't like!
Somewhere in here is a sad little story about star-crossed lovers, but it's totally overwhelmed by a cast of grotesques with revolting ways of killing people. The graphics are striking but ugly. Even the (sort of) good guys are beetle-browed and sinister. (And in fact, when I commented on this, the Mr. informed me that "there are no good guys; they're all bad guys.")
The outline of the story: a treaty has kept the Iga and Kouga ninja clans from wiping each other out. During this period of detente, Oboro of the Iga clan and Gennosuke of the Kouga clan fell in love and in fact, plan to be married. But now the treaty has been dissolved, and most members of both clans couldn't be more pleased: they promptly start killing each other.
( More ... with spoilers )