Used Pencil and Crazy Monster's Erasers are Real (Carbon Sketch Pencil)
Back in 2010 I was using charcoal pencils for most of my tumblr drawings. I really liked these ones. I bought them by the dozen and they got used up quickly. On the right kind of paper they have such a nice feel, not too smooth and not too scratchy. The charcoal makes very black lines, but it is a little dusty and crumbly.
I am trying to remember why I gave up on these, I think I never found a satisfactory way to sharpen them quickly.