Cover of Chapter 18.
Appears on these pages
The Butler, Shadowing (その執事、尾行, Sono Shitsuji, Bikō) is chapter 18 of the Kuroshitsuji manga...
Ciel on the cover of Volume 6. Ciel, on the cover of Volume 18.
Elizabeth on the cover of volume 13. Elizabeth on the preview of volume 13's cover.