yeah, kurogane is alternating between "lighthearted teenage humor" and "limitless endless darkness" so fast now that I'm having trouble telling them apart .

Though the "cute girl" factor only really consists of Saya and that girl who's not cut out to be a ninja... but I think she left ....

Then it does also have the Holy Shit! Ninjas appeal to it. Might fit the bill, but it's a little slow too.