Black Butler, Vol. 6

The cheer of the holidays has passed, but the Noah's Ark traveling
circus has been making the rounds, bringing fun and joy to children of
all ages. However, as the ringmaster's cries fade away, a disturbing
trend begins to surface in the wake of the colourful entourage. Children
seem to disappear whenever the circus packs up for its next
destination, and there are no clues...or corpses...to be found. But when the
situation calls for Ciel and Sebastian to infiltrate the big top, will
Sebastian's inhuman skills be enough to see him and his young master
through a treacherous tightrope act that may well end in death?