Can anybody recommend some manga like Kuroshitsuji/Black Butler?

I like the darker, not so "OOH! I LOVE YOU LET'S HAVE PROBLEMS THEN GET MARRIED!" kind of manga. Okay, sorry. That may have been a little overboard. I like the romantic manga and such, but I'm more prone to psychological thriller kind of manga, or ones like Kuroshitsuji. Any suggestions would be great and very much appreciated! :)